Adoption of innovative heating systems—needs and attitudes of Swedish homeowners

Questionnaire surveys of Swedish homeowners of detached houses were carried out in 2004 and 2007 to understand their needs and attitudes towards attributes of innovative heating systems (IHSs) comprised of a bedrock heat pump, district heating, or a wood pellet boiler. In each occasion 1,500 homeowners were randomly selected. The response rate was 42% in 2004 and 48% in 2007. Results showed that the majority of the respondents were satisfied with their existing heating system and did not intend to install new systems. Economic factors and functional reliability were the most important factors in the respondents’ choices of heating system, while environmental factors were of lower importance. Among the IHSs, respondents had the most favorable attitude towards bedrock heat pumps followed by district heating and pellet boilers. But the attitude was more favorable towards electric boilers than for pellet boilers. The least favorable attitude was towards oil boilers. Between 2004 and 2007, there was a positive change in respondents’ attitude towards IHSs and electric boilers, and a negative change in attitude towards resistance heaters and oil boilers.     

Neuro fuzzy model for adaptive filtering of oscillatory signals

In this paper we have developed a neuro fuzzy model for adaptive filtering of oscillatory signals embedded with white noise. Such type of fuzzy adaptive filters are constructed from a set of fuzzy IF-THEN rules, which change adaptively to minimise the cost function until a desired information is available. Here we have used a generalised cost function for better convergence of the error. This algorithm is simulated on a digital signal processor in order to track the signal and to filter out the disturbances present in the signal at a particular instant of time. The system presented here, can measure both types of information like numerical as well as linguistic.     

Influence of Alumina on Iron Ore Sinter Properties and Productivity in the Conventional and Selective Granulation Sintering Process

Iron ore sinter constitutes a major proportion of blast furnace burden. Hence, its quality and consistency have a significant impact on blast furnace performance. Iron ore fines are the main source for sinter, and the chemical composition of the iron ore fines, together with the thermal conditions that blends are subjected to, plays an important role in forming the primary melt during the sintering process and accordingly determines the sinter structure and quality. Therefore, considerable importance has been placed on the chemical composition and consistency of iron ore fines, particularly in terms of alumina content. Due to depletion of high grade iron ore resources, alumina content in the iron ore fines is expected to increase gradually. Ore with higher alumina content is usually expected to be detrimental in forming the sinter matrix, if sintered alone, due to the low reactivity of alumina bearing minerals and the high viscosity of primary melts. The selective granulation process is a new sintering process for high alumina iron ore fines, and can eliminate the adverse effects of ‘hard to sinter’ or ‘unsuitable – for ironmaking’ ores. In the present work laboratory sintering experiments have been carried out with iron ore fines of different alumina level (2.00 to 5.46 mass‐%) to know the influence of alumina on mineralogy, productivity, physical and metallurgical properties of sinter prepared by the conventional and the selective granulation process. With increasing alumina content in sinter of both the conventional and selective granulation process, the fractions of hematite and of silico‐ferrites of calcium and alumina (SFCA) as well as the pore phase increased whereas the magnetite and silicate phases decreased. With increase in alumina content sinter productivity and tumbler index (T.I.) decreased, and metallurgical properties like sinter RDI and reducibility improved. However, sinter of the selective granulation process showed better results compared to the conventional process.     

Effect of Iron Ore Pellet Size on its Properties and Microstructure

The properties of the pellets and their microstructure mainly depend on the raw material mix proportion, raw material chemical composition and the physicochemical conditions like the temperature and oxygen partial pressure within the induration machine. The pelletising plant products are in the size range of 8 to 16 mm. With increasing pellet size, the sintering intensity, thermo‐chemical conditions and formation of different phases vary across its cross section. The time required for varies reactions within the pellet is directly proportional to the pellet size. Because of differences in pellet size, the reduction and oxidation process takes place under different conditions resulting in different phases and microstructures. In this work, detailed studies were carried out on pellets of different size (8 to 16 mm) produced from a 4.2 Mtpa pellet plant for their physical, metallurgical and microstructural properties. It was observed that the pellets in the size range of +8 to ‐12 mm showed good strength and lower RDI. It was observed that the amount of hematite, magnetite, porosity, pore density, pore size and slag phase play a significant role on pellet strength and RDI.     

Inactivation of Escherichia coli K12 by pulsed UV light on goat meat and beef: microbial responses and modelling

The objective of this study was to investigate the efficacy of pulsed UV light (PUVL) in inactivating Escherichia coli K12 on goat meat and beef surfaces. Inactivation studies were conducted for 5 to 60 s at three distances from the light source (4.47, 8.28 and 12.09 cm) in the PUVL chamber. Predictive models using regression and artificial neural networks (ANN) were developed to quantify log reductions. Pulsed UV light was more effective on beef than goat meat. Maximum log reductions of 1.66 and 1.74 CFU mL⁻¹ rinse solution were achieved on goat meat and beef, respectively, at 4.47 cm distance for 60 s. Escherichia coli K12 reduction increased significantly with increasing treatment time and closer distance from the light source. In general, both ANN and regression models effectively described inactivation of E. coli K12. Predictive models describing PUVL inactivation kinetics of E. coli K12 can be used for process optimisation in meat industry.     

On the generation and recovery of hot carrier induced interface traps: a critical examination of the 2-D R-D model

The generation and recovery of interface traps (N/sub IT/) during and after hot carrier injection stress is evaluated by the recently proposed two-dimensional (2-D) reaction diffusion (R-D) model. The power law time exponent (n) of N/sub IT/ generation as well as the magnitude of fractional and absolute recovery after the stress cannot be fully explained by considering only the spatial extent of broken /spl equiv/Si-H bonds, as is done by 2-D R-D model. Additional contribution due to broken /spl equiv/Si-O bonds also plays a major role in determining the overall N/sub IT/ generation and recovery behavior.     

Photoelectrochemical cells with mixed polycrystalline n-type CdSPbS and CdSCdSe electrodes

The photoelectrochemical behaviour of n-type CdS (polycrystalline) containing small amount of PbS or CdSe in S^2? /S^2?_n redox system has been studied. Mixed polycrystalline n-type CdSPbS electrodes were prepared by electrodeposition and the n-type CdSCdSe electrodes were made by partial replacement of sulphide ions of CdS electrode with selenide ions from a solution of sodium selenosulphate. It has been observed that both the mixed chalcogenide electrodes exhibit better photoresponse than the simple CdS electrode.     

CHISEL programming operation of scaled NOR flash EEPROMs-effect of voltage scaling, device scaling and technological parameters

The impact of programming biases, device scaling and variation of technological parameters on channel initiated secondary electron (CHISEL) programming performance of scaled NOR Flash electrically erasable programmable read-only memories (EEPROMs) is studied in detail. It is shown that CHISEL operation offers faster programming for all bias conditions and remains highly efficient at lower biases compared to conventional channel hot electron (CHE) operation. The physical mechanism responsible for this behavior is explained using full band Monte Carlo simulations. CHISEL programming efficiency is shown to degrade with device scaling, and various technological parameter optimization schemes required for its improvement are explored. The resulting increase in drain disturbs is also studied and the impact of technological parameter optimization on the programming performance versus drain disturb tradeoff is analyzed. It is shown that by judicious choice of technological parameters the advantage of CHISEL programming can be maintained for deeply scaled electrically erasable programmable read-only memory (EEPROM) cells.     

Power reduction methods for NMOS dynamic random access memories

Power reduction methods for NMOS dynamic random access memories are proposed which reduce power dissipation. As the bit density increases in NMOS dynamic random access memories the power dissipation increases. A major consideration in the design of megabit dynamic random access memories is the power supply voltage. The power supply voltage mainly depends upon the following factors: power dissipation; reliability, such as high field effects due to small device size; memory cell operating margin. Power dissipation in decoders and 1 megabit NMOS dynamic random access memory chips are discussed. The basic properties of the proposed methods and a prototype VLSI implementation are discussed. In order to meet user power supply requirements, the proposed power reduction methods are useful for future megabit NMOS dynamic random access memories.     

Secure energy aware routing protocol for trust management using enhanced Dempster Shafer evidence model in multi-hop UWAN

Wireless Networks - At present, underwater wireless ad hoc networks (UWAN) are widely used in enormous applications. At the same time, UWAN faced many security issues, like energy leaks. The energy...