Artificial neural network based modelling of desiccant wheel

In this article, the concept of artificial neural network and goal oriented design have been used to propose a computer design tool that can help designers to evaluate performance of desiccant cooling system and behaviour of the desiccant wheel. Based on the experimental observations on desiccant wheel, a neural network model has been developed using a neural network toolbox of MATLAB^® with feed forward back propagation method. The model has been validated against experimental data sets. A number of training algorithms with feed forward back propagation method have been used for the modelling of desiccant wheel to identify a training algorithm with least mean square error (MSE). The performance of all training algorithms has been analyzed and training algorithm trainlm (Levenberg-Marquardt back propagation) is found most suitable for the prediction of outputs which have least mean square error of 0.064462 and 0.007575 for specific humidity and temperatures respectively. The proposed model can predict the specific humidity and temperature at the outlet of desiccant wheel within the range of experimental values.     

Patient-reported short-term and long-term physical and psychologic symptoms: results of the continuous hyperfractionated accelerated [correction of acclerated] radiotherapy (CHART) randomized trial in non-small-cell lung cancer. CHART Steering Committee

PURPOSE: The randomized multicenter trial of continuous hyperfractionated accelerated radiotherapy (CHART) versus conventional radiotherapy for patients with non-small-cell lung cancer (NSCLC) showed a significant survival benefit to CHART (29% v 20% at 2 years, P=.004). However, an assessment of the effect on physical and psychologic symptoms is vital to balance the costs and benefits of the two treatments. METHODS: A total of 356 patients in the United Kingdom completed the Rotterdam Symptom Checklist (RSCL) and the Hospital Anxiety and Depression Scale (HADS) at 10 time points. The principal aim of the analyses was to keep the methods simple, so as to allow the presentation and interpretation of the results to be as clear as possible. This was achieved by (1) considering individual symptoms rather than symptom subscales or domains, (2) assessing short-term effects (up to 3 months) and long-term effects (at 1 and 2 years) separately, and (3) for the short-term analyses, (a) splitting the data randomly into an exploratory data set and a confirmatory data set, and (b) using two different methods of analysis: a subject-specific approach, which used the area under the curve (AUC) as a summary measure, and a group-based method, which plotted the percent of patients with moderate or severe symptoms over time. RESULTS: The results indicate that apart from CHART causing transient pain on swallowing and heartburn, there was little difference between the regimens in the short or long-term. CONCLUSION: Combining the results of the patient-assessed symptom comparisons with the clinical results indicates that CHART confers a major benefit without serious morbidity.     

Enzyme‐catalyzed regioselective synthesis of sugar esters and related compounds

In this review, a comprehensive and illustrative survey is made of the regioselective synthesis of esters of sugars and related compounds using lipases. The main emphasis has been given to the screening and use of commercially available lipases for the enzymatic esterification of neutral monosaccharides, disaccharides, sugar alcohols and their selected ether and ester derivatives. The effect of solvents and solubilizing agents in improving the yields of the resultant sugar fatty acid esters has been incorporated. Further, solvent‐free esterification with molten fatty acids, use of ionic liquids and microwave radiations for improvement in the methodology have also been discussed. Copyright © 2006 Society of Chemical Industry     

A 0.9-V microcontroller for portable applications

A 0.9-1.6-V, 1-MHz, 8-b microcontroller based on the 68HC08 architecture is presented. In addition to standard digital microcontroller functions, the chip features RAM, ROM, phase-locked loop (PLL) clock synthesis, and liquid crystal displays (LCD) drive capabilities operating from the voltage supply range of a single AA or AAA battery. The design used a library of CMOS microcontroller building blocks, converted into a low-voltage technology using unilateral transistors. The design approach was to optimize the conversion strategy for each functional block and to provide new designs when the conversion was insufficient. The chip exceeded specifications with blocks showing full functionality down to 0.7 V     

Predictions of limit strains in sheet metal using a more general yield criterion

Hill has proposed a new yield criterion for anisotropic materials which is more general than the criterion previously adopted in this type of work. The criterion is used in the Marciniak-Kuczyński type model to predict the limit strains occurring in frictionless in-plane stretching. The analysis assumes that the principle of equivalence of plastic work holds and it will be necessary to check this assumption for individual sheet metals. The analysis is particularly useful for describing the plastic behaviour of materials with r-values less than unity and it is shown that the high limit strains previously predicted for soft aluminium do not occur.     

Preparation, characterization, and stability of liposome-based formulations of mitoxantrone

The preparation, characterization, and stability of lyophilized liposome-based formulation of mitoxantrone was investigated. Mitoxantrone was entrapped inside small, unilamellar liposomes composed of dioleoylphosphocholine (DOPC), cholesterol, and cardiolipin. The mean vesicle size and drug entrapment efficiency of the liposomes were ~ 150 nm and ~ 99%, respectively. Less than 1% of drug was lost and mean vesicle size remained unchanged after sterile filtration. The pre-lyophilized (pre-lyo) formulations were characterized by a differential scanning calorimetric (DSC) method. Results showed that the glass transition temperatures (Tg') increased as the molar ratios of sucrose:lipid and trehalose:lipid in the formulations were increased. The maximum Tg' of the pre-lyo formulations containing 10:1 sucrose:lipid and trehalose:lipid molar ratios were - 37°C and - 41°C, respectively. After reconstitution of the lyophilized cake of the sucrose-containing formulation, the mean vesicle size was comparable to pre-lyo liposome size. In vitro release studies showed that less than 2% of mitoxantrone was released after an extensive dialysis against phosphate buffered saline (PBS) at 37°C, indicating that the mitoxantrone was highly associated and retained inside the liposomes. Short-term stability studies of the sucrose-containing formulations revealed that the reconstituted and eight-fold diluted formulations were stable for up to 8 hours at room temperature. Long-term stability studies of lyophilized liposomal mitoxantrone showed that the lyophilized formulation was stable for up to 13 months after storage at refrigerated condition.     

Efficient wireless reprogramming through reduced bandwidth usage and opportunistic sleeping

Wireless reprogramming of a sensor network is useful for uploading new code or for changing the functionality of existing code. Reprogramming may be done multiple times during a node’s lifetime and therefore a node has to remain receptive to future code updates. Existing reprogramming protocols, including Deluge, achieve this by bundling the reprogramming protocol and the application as one code image which is transferred through the network. The reprogramming protocol being complex, the overall size of the program image that needs to be transferred over the wireless medium increases, thereby increasing the time and energy required for reprogramming a network. We present a protocol called Stream that significantly reduces this bloat by using the facility of having multiple code images on the node. It pre-installs the reprogramming protocol as one image and equips the application program with the ability to listen to new code updates and switch to this image. For a sample application, the increase in size of the application image is 1 page (48 packets of 36 bytes each) for Stream and 11 pages for Deluge. Additionally, we design an opportunistic sleeping scheme whereby nodes can sleep during the period when reprogramming has been initiated but has not yet reached the neighborhood of the node. The savings become significant for large networks and for frequent reprogramming. We implement Stream on Mica2 motes and conduct testbed and simulation experiments to compare delay and energy consumption for different network sizes with respect to the state-of-the-art Deluge protocol.     

Sensitivity Optimization of MEMS Based Piezoresistive Pressure Sensor for Harsh Environment

Silicon - Silicon carbide piezoresistive pressure sensor is more suitable for harsh environment due to its wide bandgap, corrosion tolerance, excellent chemical inertness, high Young’s...     

Non-blind Arnold scrambled hybrid image watermarking in YCbCr color space

Microsystem Technologies - Due to fast technological development, human beings generally depend upon computer and other digital equipments in different areas of concern/applications. Therefore,...     

A new approach for simplification and control of linear time invariant systems

Microsystem Technologies - This study presents a new approach for system simplification and control. This approach is based on the behaviour of growth and reproduction of weed plants namely...