Management system requirements for wireless systems beyond 3G

This paper presents a comprehensive description of various management system requirements for systems beyond 3G, which have been identified as a result of the Software Based Systems activities within the Mobile VCE Core 2 program. Specific requirements for systems beyond 3G are discussed and potential technologies to address them proposed. The analysis has been carried out from network, service and security viewpoints

Agriculture and The Challenge to Reduce Poverty in East Africa

The three East African (EA) countries Tanzania, Kenya and Uganda have a population of about 95 million people and Gross Domestic Product (GDP) of USD 34.2 billion. In recent years efforts has been made among the three East African countries, towards forging economic and regional co-operation by establishing the East African Community (EAC). The premise for economic and regional co-operation has been underpinned for the need for a common market and boost regional trade. The ultimate goal of these efforts is to achieve one of the international development objectives of increasing growth to 7% a year that is required to reduce income poverty. One of the challenges that East African countries need to tackle in the face of globalisation is the ability to participate in international markets. East African countries have to make serious consideration with regards to changing the composition of their exports away from primary products to manufactured exports. Value addition to both agricultural and industrial products is vital to improving the EA economies. This paper examines the composition of East Africa’s economic structure. The aim is to analyse how the economic structure has changed over time, and to assess whether or not East African countries have transformed their agricultural sectors, and what the impact has been on poverty reduction in these economies.Agricultural and Food Policy, Community/Rural/Urban Development, Environmental Economics and Policy, Farm Management, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, International Relations/Trade, Land Economics/Use, Marketing, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies,

Backscatter Transponder Based on Frequency Selective Surface for FMCW Radar Applications

This paper describes an actively-controlled frequency selective surface (FSS) to implement a backscatter transponder. The FSS is composed by dipoles loaded with switching PIN diodes. The transponder exploits the change in the radar cross section (RCS) of the FSS with the bias of the diodes to modulate the backscattered response of the tag to the FMCW radar. The basic operation theory of the system is explained here. An experimental setup based on a commercial X-band FMCW radar working as a reader is proposed to measure the transponders. The transponder response can be distinguished from the interference of non-modulated clutter, modulating the transponder’s RCS. Some FSS with different number of dipoles are studied, as a proof of concept. Experimental results at several distances are provided

Nano-silica production by a sustainable process; application in building materials.

Concrete is the most widely produced manmade material. Current micro-silica is only applied in special cases, due to its high price, and nano-silica is not used in common practice yet. The neutralization of waste acids (either sulphuric or hydrochloric) with olivine produces tailored nano-silica [1][2]. The main factors that determine the rate of dissolution of olivine in acids at elevated temperatures are the olivine specific surface area, the temperature and the pH. The production parameters with a strong influence on the properties of the silica are the olivine composition and fineness, acid purity and concentration, temperature, releases of silica monomers rate and stirring speed. Nano-silica obtained by this process can be produced in large quantities, for low prices and by sustainable method so that mass application in concrete is within reach. It may replace cement in the mix, which is the most costly and environmentally unfriendly component in concrete. The use of nano-silica reduces the CO2 footprint of the manufactured concrete products and improves the properties in hardened state. Thus a concrete with better performance, lower costs and environmentally sustainable is designed. The application of these concretes can be anywhere, both in infrastructure and in buildings

Superparamagnetic particles in ZSM-5-type ferrisilicates

As-synthesized, low iron content, ferrisilicates of ZSM-5-type contain well-separated Fe(III) ions in a tetrahedral environment and display paramagnetic behavior. After hydrothermal treatment, the iron ions are partially extracted from the framework, generating nanosize iron oxide or oxyhydroxide ferrimagnetic particles. This process has been studied by transmission electron microscopy (TEM), Mossbauer spectroscopy, magnetic ac susceptibility (chi(ac)), and field dependent magnetization, on samples containing up to 6.7 wt. % Fe. The experiments evidence the growth of nonaggregated particles, with a typical size around 3 nm, presumably located at the surface of the ferrisilicate crystallites, From a thorough granulometric analysis involving TEM and chi(ac) data, it is concluded that, in the range from 1.5 to 4.6 wt. % Fe, the particle size distributions are significantly independent of the iron content

Viability of Consumer Grade Hardware for Learning Computer Forensics Principles

We propose utilizing budget consumer hardware and software to teach computer forensics principles and for non-case work, research and developing new techniques. Consumer grade hardware and free / open source software is more easily accessible in most developing markets and can be used as a first purchase for education, technique development and even when developing new techniques. These techniques should allow for small forensics laboratories or classroom settings to have the tooling and framework for trying existing forensics techniques or creating new forensics techniques on consumer grade hardware. We\u27ll be testing how viable each individual piece of hardware is as well as combinations along with seeing at which point utilizing forensics-grade hardware becomes necessary in order to proceed

Development of the particle and pore structure of silica below the isoelectric point

Nano-silica is one of the most used nano-materials, and its use is rising 5.6% per year to reach a projected 2.8 million metric tons in 2016 with a value of $6.4 billion. The current production methods involve steps with high temperatures resulting in environmentally unfriendly and expensive process. The production of nano-silica by the dissolution of olivine is an interesting alternative to the existing commercial methods because of the good quality of the resulting silica and low energy requirements and CO2 emissions. Olivine nano-silica is produced in a very acidic environment, much more acidic than the isoelectric point of the silica. The particle and pore structure development of silica under these acidic conditions has only been studied by a few researchers. The main aim of this study is to develop a model about the particle and pore formation of silica in very acidic environments. Nano-silicas prepared via the olivine route were analyzed to determine their pore structure and SSANMR. The pore structure was determined using the nitrogen physisorption, NMR and PALS (positron annihilation spectroscopy) techniques. The development of the nano-silica structure during the olivine process can be described by the following steps: 1) initially, soluble silica nucleates and primary particles of around 2 nm are formed; 2) the silica particles grow via a condensation route, forming linear chains; 3) as the growth continues, the silica particles keep increasing in size, resulting in 3D networks; and 4) with time, the aggregates become bigger and more compact. The final result of the olivine process is agglomerates as big as 20 ¿m. In addition, internal pores (also called closed pores) are developed with the reaction conversion degree as the result of condensation of two blocks of silica particles

Particle growth of nano-silica below the isoelectric point

Nano-silica is one of the most used nano-materials, and its use is rising 5.6% per year to reach a projected 2.8 million metric tons in 2016 with a value of $6.4 billion. The current production methods involve steps with high temperatures resulting in environmentally unfriendly and expensive process. The production of nano-silica by the dissolution of olivine is an interesting alternative to the existing commercial methods because of the good quality of the resulting silica and low energy requirements and CO2 emissions. Olivine nano-silica is produced in a very acidic environment, much more acidic than its isoelectric point. The particle growth of silica under these acidic conditions has only been studied by a few researchers. The main aim of this study is to clarify the mechanism and kinetics of the silica particle growth under these conditions. The silica particle growth was studied with Norwegian olivine in a vigorously stirred reactor at 20 °C with sulfuric acid. The concentration of hydrogen ions was determined at regular time intervals, from which the amount of silica produced was calculated. The silica particle size was measured with the Malvern ZS after passing the samples through a filter of 1 ¿m. The cluster size of olivine silica grows up to 420 nm after 4300 minutes of reaction at 20 ¿C in 2M H2SO4 solution. The mechanism of the growth of silica is likely due to the nucleation of primary particles and subsequent aggregation of these primary particles. Olivine nano-silica does not gel. This behaviour can be due to three reasons: 1) silica polymerizes fast at 90 ¿C in 3M H2SO4 solution, forming particles above 100 nm in a short time; 2) the concentration of small silica colloids is low; and 3) the vigorous mixing in the reactor to keep the olivine particles suspended