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In applications where the water hardness and TDS were marginally higher, the nano-filtration membrane came in very handy due to its ability in reducing the permeate TDS at reasonable energy cost. In this work, a thin nanofiltration membrane formed by M-phenylenediamine (MPD) and trimesoyl chloride (TMC) and coated on both sides of a polyacrylonitrile (PAN) membrane. Interfacial polymerization method was used for the nano-film formation. Tests showed that thick monomers solution and denser PAN structure would lead to a membrane of better solutes rejection.

In a MBR system, huge amount of solid suspension clogged the membrane and reduced the permeate flux. Mechanical motions were believed to be effective in preventing premature clogging of the membrane. Three different mechanical motions; namely cross oscillation, lengthwise oscillation and the VSEP were investigated. The VSEP combined mechanical motion and the high trans-membrane pressure achieved the best GFD for MBR membrane filtration.

In dealing with the fine carbon loaded wastewater from a TV picture tube plant, the technique of vibration membrane was proven to be a more effective means than the conventional coagulation and settlement method. The present work is to look into the characteristics of the carbon particle sizes and the membrane pore sizes in the performance of the vibration membrane. The parameters taken into consideration in this work include membrane types, particle sizes, particles concentration, trans-membrane pressure, vibration amplitude and feed temperature. The studies showed that one could achieve a higher permeate flux and less frequent back wash through a suitable match of particle size and membrane type.

A test rig was designed and fabricated in this project to study the heat transfer of falling film flow on a doubly fluted plate. Parametric studies were performed to test the thermal performance based on the measured data. The effects of the temperature difference and feed water flow rate were studied with a given steam flow rate. The effect of steam flow rate was also studied under fixed feed water flow rate. During the testing, dry patches appeared on the plate surface when the feed water flow rate was less than 350 l/h. The measured results show that lower temperature difference, lower feed water flow rate and higher steam flow rate can increase the overall heat transfer coefficient. However, the effect of the temperature difference may have larger effect than that of the steam flow rate. This experiment results provide a good clue in the design of vertical tube falling film evaporators.

An experimental system with a transparent flash evaporation chamber was set up in this work to simulate the single-phase seawater flow in the flash stage in the multi-stage flash (MSF) desalination process. The flash evaporation chamber is 300 mm in height × 823.8 mm in length × 40 mm in width and was designed to be able to run under flash evaporation flow conditions. The whole field fluid flow velocity vectors in the chamber were measured using a particle image velocimetry (PIV) system to study the effects of main flow parameters such as water level and flow rate on flow patterns. The fluid flow in the chamber was also numerically simulated using a two-dimensional k-epsilon turbulent flow model. The measured free surface profiles and inlet gate velocity distributions were used as the boundary conditions. The streamlines were generated directly from the velocity vectors using the TECPLOT software package. The simulated results were compared with the measured data. The results show that a large recirculation region with several vortices embedded would be generated at a higher water level or at a larger flow rate.

Flow characteristics inside a model flash evaporation chamber for Multi-stage Flash (MSF) desalination have been investigated using Particle Image Velocimetry (PIV). The back flow region near the inlet gate, the free water surface shape, and the overall velocity distribution were measured so as to identify the characteristics of the flow pattern at different water levels in the chamber. The results show that a large recirculation region with several vortices embedded would be generated at a higher water level (approximately twice the inlet gate height). The water level remained uniform in spite of the presence of the vortices. Three flash evaporation modes at different superheats of the water in the flash chamber were also studied using a high speed CCD camera. The bubble behaviors such as the size, velocity, and growth rate were estimated and analyzed. It was found that the multi-phase flow pattern during the flash evaporation was mainly determined by the liquid superheat and the nuclei distribution.

We document the pathological characteristics of 135 cancers detected in 132 predominantly Chinese women in the Singapore breast screening project. Thirty-four (25%) screen detected tumours were in situ ductal cancers; 98 (73%) invasive, while three (2%) women with malignant fine needle aspirate smears refused further treatment. The median size of in situ cancers was 10 mm; the majority (56%) demonstrated a comedo pattern. Of the invasive tumours which had a median size of 15 mm, three (3%) were microinvasive, 75 (77%) infiltrative ductal, three (3%) invasive lobular, and the remaining 17 (17%) special types or others. Histologic grading revealed 23 (24%) grade I, 52 (53%) grade II, 19 (19%) grade III and four (4%) ungraded cases. Sixty-three (65%) of the invasive cancers were node negative, while 64% of all screen detected malignancies were Stages 0 (in situ) or I. From the pathological perspective, problems of borderline lesions, microinvasion, grade assessment and histological subtyping have to be addressed.

Vacuum desalination is a process by which water is vaporized at a lower temperature when subjected to vacuum pressure. The heat energy requirement for desalination using a distillation process can be brought down by reducing the boiling temperature. The boiling temperature of seawater can be lowered to as low as 400°C by the creation of a vacuum. Using waste heat from a steam turbine, a pilot study was conducted in the laboratory to investigate the feasibility of using a vacuum desalination process for water supply. The treatment system is designed to minimize the heat requirement. Initially, the seawater is converted to a wet steam in a saturated vapour heater. This vapour heater receives heat from the superheated steam which is due for condensation. The dry component of the wet steam is heated to superheated condition by a superheated vapour heater. This superheated vapour heater receives heat from the waste heat from a steam turbine. Superheated vapour is used to covert incoming seawater to wet steam and then be condensed as the product of the system for potable use. The investigation shows that a vacuum desalination system using turbine exhaust waste steam is possible and has several advantages. Seawater can be boiled at a lower temperature and thus save in energy consumption. Based on experimental results, water boils at 40–90°C at the corresponding vacuum pressure of 0.1–0.7 bar, respectively. The consumption of heat from the waste steam is minimized as the superheated vapour is used to heat the influent seawater. Most of the heat from the waste heat is required to compensate for the heat losses in the system. The energy efficiency of the system depends very much on decreasing the heat losses from the system. It is possible to use nonconventional energy sources such as lower pressure waste steam for vacuum desalination. Hard scale formation in the system can be minimized as scale forming is the major problem in a high temperature distillation process. The qualities of distillates are excellent.

In this study, a commerical finite element package ‘MSC/NASTRAN’ was used to investigate the vibration behaviour of honeycomb structures with disbonds. The honeycomb structure was modelled as a three-layer substructure with the use of 3-D solid polyhedron elements (CPENTA and CHEXA). Dynamic analysis of free undamped vibration was undertaken to study the natural frequencies of the honeycomb structures. A mesh dependency study was carried out to decide upon the optimum mesh density. With the selected mesh, computations were performed to calculate the natural frequencies of eight honeycomb structures with free edges or combinations of free and fixed edges. The predicted results are presented and the influence of different boundary conditions, as well as different geometries of the structures, on the predictions are discussed. Conclusions on the effect of these factors are highlighted in the final section.

In this study, the finite element method was used to compute the frequency responses of honeycomb structures with disbond (delamination). The honeycomb structure was modelled as a three-layer substructure with the use of a three-dimensional solid polyhedron element. The real eigenvalue analysis and frequency response analysis were undertaken to study the natural frequency, amplitude and phase of dynamic response of the honeycomb structures. With the selected mesh, computations were performed to obtain the natural frequency, amplitude and phase of honeycomb structures with free edges or combinations of free and fixed edges. The influence of different boundary conditions as well as different geometries of the structures on the predictions is discussed. In addition the influences of applied force, skin thickness and adhesive thickness on these parameters are investigated. Conclusions on the effects of these factors are highlighted.

The use of the mechanical impedance method for nondestructive testing and analysis of honeycomb structures is described. This technique is frequently used in aircraft maintenance to test the bond or disbond of honeycomb structures. The mechanical impedance instruments, MIA 3000, Versiscan and VP 200, are used for the testing. In the analysis, a defect area of honeycomb structure was modelled as a spring, mass and damping system, so that its resonance frequency is unique to the structure. According to theory and experimental observation, the resonance frequency of a disbond area is lower than that of the perfect bond area. Therefore this resonance frequency may be used to examine the bonding of structures for disbond areas. By using different test frequencies, different amplitudes or phases of impedance can be determined. It is found that with low test frequency, disbond areas can be clearly shown by the amplitude variation. However, if the test frequency is higher than the resonance frequency of the perfect bond area, the amplitude or phase of impedance cannot effectively show a disbond. It has also been found that if the test frequency is slightly lower than the resonance frequency of the perfect bond area, the impedance phase is the best indicator of the defect area.

The effects of disbond (delamination) sizes and skin thicknesses on the dynamic response of honeycomb structures were investigated. A mechanical impedance instrument (MIA 3000) was used to test the specimens which were made of two layers of thin aluminium skins with Nomex honeycomb cores. Firstly, this study concentrated on the influence of disbond size on its resonance frequency and the amplitude and phase of impedance in honeycomb structures. Secondly, the influences of skin and honeycomb core thicknesses on these parameters were also investigated. It was found that, having the same skin thicknesses and materials, the resonance frequency of a large disbond was lower than that of a small disbond, and also lower than that of a good area. With a thicker skin, the resonance frequency was higher than that of a thinner skin. It was also observed that, with a thicker honeycomb core, the resonance frequency in a good area was larger than in that of a thinner one. The resonance frequency in a constant disbond, however, was invariant when the skin thicknesses and materials were kept the same. It was further evident that, with a swept frequency ranging from 1 to 8 kHz, most disbonds could be detected if the thicknesses of aluminium skin were between 0.5 and 2.0 mm.

The process reported is known as vacuum desalination. This technique takes advantage of the drop in boiling point of sea water if pressure is reduced. By doing so, the temperature of a turbine exhaust steam is sufficiently high to cause boiling of sea water at the pressure of about 10 kPa. The system comprises of a saturated vapour heater and superheated vapour heater. Initially, the sea water is converted to a wet steam in the saturated vapour heater after receiving heat from a superheated steam which is due for condensation. The dry component of the wet steam is then channelled to the superheated vapour heater and is heated to superheated condition by the turbine waste steam. The system is designed in such a way that heat from the superheated steam is reused for heating up the incoming sea water in the saturated vapour heater. The consumption of heat from the turbine waste steam is kept to a minimum and most of which is to compensate for heat losses in the system. In the saturated vapour heater, the superheated steam after rejecting its latent heat to the incoming sea water is condensed and is pumped out from the system by a positive displacement pump.

We describe for the first time, a miniature GPS front-end module that achieves state-of-the-art gain and filtering in a single package. The module combines a E-mode pHEMT LNA MMIC with FBAR filter chip in a molded chip-on-board plastic package. At 2.7V supply voltage and 5mA current consumption, overall gain achieved is 18dB with 0.82dB noise figure. Filter rejection is better than 76dBc in the 827MHz and 65dBc in the 1.885GHz cellular frequency bands. The module is immune to interfering signals up to −3.7dBm at the above frequencies, more than adequate to prevent gain compression in a S-GPS environment. The complete chip is housed in a 2-layer BTNX green material PC board and occupies an area of (3.3 × 2.1)mm.

An engine-cylinder-pressure-damping device has been designed to reduce engine noise by controlling the sharp pressure-rise excitation applied to the engine structure by the combustion process. The device is a small piston controlled by a spring-and-dashpot system connected to the engine cylinder by mounting it on top of the cylinder head. Laboratory tests showed that there was a significant reduction in engine surface vibration and noise radiated, particularly at high frequencies above 4000 Hz.

Background The alpha and beta subunits of FSH were fused to the Fc domain of IgG1 either in a single chain or a heterodimer format. These molecules were absorbed through the epithelium in lung and intestine by neonatal Fc receptor (FcRn)-mediated transcytosis. Methods and results Single chain and heterodimer FSH-Fc were made recombinantly in Chinese hamster ovary cells. Treatment of rats with a single s.c. dose of single chain or heterodimer FSH-Fc resulted in greater stimulation of ovarian weight (20.8+/-3.9 and 26.9+/-6.1 mg respectively) compared to those receiving vehicle (12.1+/-1.0 mg) or an equimolar dose of recombinant human FSH (14.3+/-1.7 mg). Both FSH-Fc fusion proteins were absorbed after oral dosing of newborn rats with long terminal half-lives of approximately 60 h, and pulmonary delivery in four cynomolgus monkeys produced maximum serum concentrations between 69 and 131 ng/ml with long terminal half-lives between 55 and 210 h. Serum inhibin levels increased after pulmonary dosing with single chain FSH-Fc (1.3- and 1.4-fold) and heterodimer FSH-Fc (5.9- and 7.1-fold) and remained elevated for >12 days after treatment with heterodimer FSH-Fc. Conclusions We have shown that FSH-Fc fusion proteins have increased stability in blood and improved bioactivity in vivo, and that heterodimer FSH-Fc is more active in rats and monkeys than single chain FSH-Fc. These data suggest that Fc fusion proteins offer the potential for oral and pulmonary delivery of FSH.

Grid computing seeks to aggregate computing resources within an enterprise and leverage on resources not owned for compute-intensive applications. Geo-rectification is a process for correcting spatial location and orientation of a satellite image. This paper focuses on the parallelization of the compute-intensive satellite image geo-rectification problem on a cluster Grid. We discuss our approach to data and task partitioning, visualization technique and the archival of data. The computational tasks include wrapping satellite positional data to compensate the Earth curvature, and consist of several steps such as image re-sampling, resolution conversion and image matching. Experimental results obtained using commodity PC are discussed.

The authors describe how the Electromagnetic Transients Program (EMTP) can be used as a tool to evaluate the effectiveness of active power line conditioners (APLC) in reducing harmonic distortion in distribution systems. The system under study consists of a three-phase diode bridge rectifier served by three single-phase distribution transformers. A shunt APLC and/or shunt passive power filters (PPFs) are used to reduce harmonic distortion. Special attention is given to the shunt APLC rating when it is used with shunt PPFs for harmonic distortion reduction. >

Conventional coagulation and settlement method was used for the treatment of fine carbon loaded wastewater from TV picture tube plants. The method is generally costly and large amount of solid waste was created. The application of vibration membrane to deal with this kind of wastewater is proven to be cost effective. The recovered water can be reused and the concentrated fine carbon is likely to be recycled back to the production process. This work reports a parametric study on water recovery from the fine carbon loaded wastewater using the vibration membrane. Parameters considered are the type of membrane, vibration characteristics, loading particle size and concentration.

Studies of fuel droplets entrained in air flow are deemed to be important in the understanding of fuel transportation and evaporation in the induction system of spark-ignition engines. So far the studies by other authors were restricted to steady air flow, however, the air flow in the induction system is pulsative unsteady air flow. This paper presents a theoretical model and the computational solution for the fuel liquid droplets entrained in the transient unidimensional air flow in a pipe.

Modele d'un ecoulement diphasique unidirectionnel transitoire et son application a un moteur a allumage par etincelle