Dynamic analyses of liquid storage tanks

Theoretical and experimental investigations of the dynamic behavior of cylindrical liquid storage tanks are conducted to seek possible improvements in the design of such tanks to resist earthquakes. The study is carried out in three phases: 1) a detailed theoretical treatment of the liquid-shell system, 2) an experimental investigation of the dynamic characteristics of full-scale tanks, and 3) a development of an improved design-procedure based on an approximate analysis. Natural frequencies of vibration and the associated mode shapes are found through the use of a discretization scheme in which the elastic shell is modeled by finite elements and the fluid region is treated as a continuum by boundary solution techniques. In this approach, the number of unknowns is substantially less than in those analyses where both tank wall and fluid are subdivided into finite elements. A method is presented to compute the earthquake response of both perfect circular and irregular tanks; it is based on superposition of the free lateral vibrational modes. Detailed numerical examples are presented to illustrate the applicability and effectiveness of the analysis and to investigate the dynamic characteristics of tanks with widely different properties. Ambient and forced vibration tests are conducted on three full-scale water storage tanks to determine their dynamic characteristics. Comparison with previously computed mode shapes and frequencies shows good agreement with the experimental results, thus confirming the reliability of the theoretical analysis. Approximate solutions are also developed to provide practicing engineers with simple, fast, and sufficiently accurate tools for estimating the seismic response of storage tanks

MODELLING THE FISHERIES OF LAKE MANZALA, EGYPT, USING PARAMETRIC AND NON-PARAMETRIC STATISTICAL METHODS

Much attention has been given to the economic aspects of the fisheries in Egypt, while building a statistical or mathematical model for fish production has received little attention. This study is devoted to a comprehensive assessment of Lake Manzala fisheries; past, present and future. Lake Manzala is one of the main fisheries resources in Egypt, and there is evidence that the fisheries have been over-exploited in recent years. The study objectives were to determine the factors that affect fish catches by individual vessels, to compare between parametric and non-parametric models of the fish catches, and to produce a mathematical model of stock behaviour which can be used to suggest policies to manage the Lake Manzala fishery. A new method of estimating the carrying capacity of the lake and intrinsic growth rate of Tilapia and its four species has been developed. Simulation had to be used to get error estimates of the biomass parameter estimates using the new method. Three catch strategies have been investigated and assessed, with discounted utility of future yields. Two ways of modelling individual vessel catches in relation to their effort characteristics, a parametric and non-parametric analysis, have been investigated. Using generalised additive model gave an improved fit to the survey data compared with the parametric analysis. It also gave a lower allowable fleet size which leads to more conservative management policy. A simulation approach was used to investigate the uncertainty in the predicted catches and stock levels, and to give insight into the risks associated with various levels of control. There was no evidence that a management strategy which aimed to fish at maximum sustainable yield would put the stock at risk

Heuristic Approach for Scheduling Dependent Real-Time Tasks

Reducing energy consumption is a critical issue in the design of battery-powered real time systems to prolong battery life. With dynamic voltage scaling (DVS) processors, energy consumption can be reduced efficiently by making appropriate decisions on the processor speed/voltage during the scheduling of real time tasks. Scheduling decision is usually based on parameters which are assumed to be crisp. However, in many circumstances the values of these parameters are vague. The vagueness of parameters suggests that to develop a fuzzy logic approach to reduce energy consumption by determining the appropriate supply-voltage/speed of the processor provided that timing constraints are guaranteed. Intensive simulated experiments and qualitative comparisons with the most related literature have been conducted in the context of dependent real-time tasks. Experimental results have shown that the proposed fuzzy scheduler saves more energy and creates feasible schedules for real time tasks. It also considers tasks priorities which cause higher system utilization and lower deadline miss time

Geotechnical and environmental effect of oily wastewater on erbil soils

Bu çalışma, rafinerilerin çıkışından kaynaklanan ve arıtma işlemi uygulanmaksızın deşarj edilen petrol içeren atıksu tarafından kirlenmiş toprakların çevre ve jeoteknik özelliklerini araştırmaktadır. Çalışma alanı ise Erbil şehrinin güneydoğusunda yer alan Kawergosek rafinerisidir. Çevresel araştırmalar da bu çalışmaya dahil edilmiş olup, anket sonuçları petrol sahalarının ve rafinerilerin yakınında yaşayan vatandaşların çoğunun hava ve toprak kirliliği sorunlarını önemsemesi gerektiğini göstermiştir (Şekil 5.5). Aynı zamanda şehir havası da CO ve H2S gibi zararlı gazlar tarafından kirlenmiş olup, çevredeki tarım arazileri de kirlenmiş ve vatandaşların hayatı üzerinde kötü bir etkiye neden olmaktadır. Erbil şehrinin güneybatısındaki çevre kirliliği haritası, petrol sahalarının ve rafinerilerin çoğunun bulunduğu yerleri de kapsayacak şekilde bu çalışmada tasarlanmıştır (Şekil 5.4). Yapılan çalışma, petrol sahalarındaki H2S emisyon oranının rafinerilerden çok daha yüksek olduğunu göstermiştir (Şekil 5.2). Aynı zamanda çalışmada, petrol içeren atık su ile çeşitli kirlenme yüzdelerine sahip toprak numuneleri üzerinde laboratuvar araştırmaları yapılmıştır. Sonuçlar, petrol içeren atıksuyun, toprağın kimyasal özellikleri üzerinde ve ayrıca Kawergosek rafineri tesisinin toprağının fiziksel ve kimyasal özellikleri üzerinde önemli bir etkiye sahip olduğunu göstermiştir. Bununla birlikte, çalışmada petrol içeren atıksu ile kirlenmiş zemin için model çukur oluşturularak saha incelemeleri de yapılmıştır. Yapılan saha incelemeleri Cihan üniversitesi/Mühendislik Fakültesi arazisinde ve Kawergosek rafineri sahası içerisinde bulunan lagün kenarında yapılmıştır. Elde edilen sonuçlar incelenen toprağın kimyasal ve mühendislik özelliklerinin petrol içeren atıksu ile kirlenmesi neticesinde oldukça etkilendiğini göstermiştir. Bir diğer çalışmada ise, petrol içeren atıksuyun toprak içerisindeki yayılımı üzerine yükseklik farkının etkisi incelenmiştir. Bu amaçla farklı yüksekliklerde üç adet model çukur oluşturulmuş olup, yükseklik arttıkça difüzyon hızının da arttığı ve direk kesme testleri ile C ve Φ üzerinde küçük bir etksinin olduğu tespit edilmiştir

An Efficient Cache Organization for On-Chip Multiprocessor Networks

To meet the growing computation-intensive applications and the needs of low-power, high-performance systems, the number of computing resources in single-chip has enormously increased. By adding many computing resources to build a system in System-on-Chip, its interconnection between each other becomes another challenging issue. In most System-on-Chip applications, a shared bus interconnection which needs an arbitration logic to serialize several bus access requests, is adopted to communicate with each integrated processing unit because of its low-cost and simple control characteristics. This paper focuses on the interconnection design issues of area, power and performance of chip multi-processors with shared cache memory. It shows that having shared cache memory contributes to the performance improvement, however, typical interconnection between cores and the shared cache using crossbar occupies most of the chip area, consumes a lot of power and does not scale efficiently with increased number of cores. New interconnection mechanisms are needed to address these issues. This paper proposes an architectural paradigm in an attempt to gain the advantages of having shared cache with the avoidance of penalty imposed by the crossbar interconnect. The proposed architecture achieves smaller area occupation allowing more space to add additional cache memory. It also reduces power consumption compared to the existing crossbar architecture. Furthermore, the paper presents a modified cache coherence algorithm called Tuned-MESI. It is based on the typical MESI cache coherence algorithm however it is tuned and tailored for the suggested architecture. The achieved results of the conducted simulated experiments show that the developed architecture produces less broadcast operations compared to the typical algorithm

High level behavioural modelling of boundary scan architecture.

This project involves the development of a software tool which enables the integration of the IEEE 1149.1/JTAG Boundary Scan Test Architecture automatically into an ASIC (Application Specific Integrated Circuit) design. The tool requires the original design (the ASIC) to be described in VHDL-IEEE 1076 Hardware Description Language. The tool consists of the two major elements: i) A parsing and insertion algorithm developed and implemented in 'C'; ii) A high level model of the Boundary Scan Test Architecture implemented in 'VHDL'. The parsing and insertion algorithm is developed to deal with identifying the design Input/Output (I/O) terminals, their types and the order they appear in the ASIC design. It then attaches suitable Boundary Scan Cells to each I/O, except power and ground and inserts the high level models of the full Boundary Scan Architecture into the ASIC without altering the design core structure

Small Business Owners’ Perception of Balanced Scorecard for Business Survival and Growth

The United States Small Business Administration (SBA) defines Small Business Enterprises (SMEs) business establishments that are independently owned managed or operated. Small business organization indicates that some of them have found the Balanced Scorecard to be very significant in boosting general performance in two key perspectives: higher complexity and management capability and drives change and enhance rapid growth. However, in the recent past, there has been increased study on the adoption of BSC in small organizations. The objective of this study was to determine the how small business owners in the United States perceive the aspects of balance score card in regard to business survivability, growth and competitiveness. Hypotheses that were to be answered include H1: Small business owners’ perceive learning and growth as the most significant perspective for their business survival, growth, and competitiveness beside the financial perspective. H2: Small business owners’ perceive customers as the most significant perspective for business growth, survival, and competitiveness. H3: Small businesses owners perceive internal business processes as the most significant perspective for their business growth, survival, and competitiveness. The philosophy adopted is positivist with explanatory and descriptive strategies. The approach of the research is quantitative using ANOVA analysis. The 100 sample companies were selected from the Best 100 small business in the SBA website and survey questionnaire sent online to this selected companies. The result of the research indicated that the most significant Balanced Scorecard perspective is the customer. At the end of the research, it was deciphered that all initiatives that the small business listed in SBA undertake when applying the BSC, customer focus is always the guiding force. Therefore, it can be stated overly that there a significant positive perception of the Balanced Scorecard as a tool to enhance growth and survivability among small businesses

Sjögren Syndrome Complicated by Mucosa-Associated Lymphoid Tissue Lymphoma and Lymphocytic Interstitial Pneumonia.

Sjögren syndrome (SS) is an autoimmune disease with exocrine glands dysfunction and multiorgan involvement. It is associated with increased risk of lymphoproliferative disorders, especially B-cell marginal zone lymphoma. While the role of F-18 Fluorodeoxyglucose position emission tomography/computed tomography (F-18 FDG PET/CT) for evaluation of lymphoma has been established, its use in patients with a chronic history of SS to evaluate for possible lymphoproliferative disorders or multiorgan involvement is limited. We present a case of chronic SS in which F-18 FDG PET/CT demonstrated FDG avid intraparotid and cervical lymph nodes pathologically proven to be mucosa-associated lymphoid tissue lymphoma. In addition, the patient had bibasilar cystic changes consistent with lymphocytic interstitial pneumonia