Oxidation of sulphide in kraft black liquor and green liquor by residual oxygen in flue gas during precarbonation

Kraft black liquor/green liquor was continuously recirculated in a column (diameter 100 mm, height 450 mm) packed with 16-mm polypropylene Pall rings countercurrent to a gas stream containing N2 and O2 (O2–3.7%). The concentration of sulphide in the green liquor was not affected by oxygen in the gas; the latter, however, completely oxidised the sulphide in kraft black liquor over an 8 h recirculation period.     

An autocorrelation-based time domain analysis technique for monitoring perfusion and oxygenation in transplanted organs

In designing an implantable sensor for perfusion monitoring of transplant organs the ability of the sensor to gather perfusion information with limited power consumption and in near real time is paramount. The following work was performed to provide a processing method that is able to predict perfusion and oxygenation change within the blood flowing through a transplanted organ. For this application, an autocorrelation-based algorithm was used to reduce the acquisition time required for fast Fourier transform (FFT) analysis while retaining the accuracy inherent to FFT analysis. In order to provide data proving that the developed method is able to predict perfusion as accurately as FFT two experiments were developed isolating both periodic and quasi-periodic cardiac frequencies. It was shown that the autocorrelation-based method was able to perform comparably with FFT (limited to a sampling frequency of 300 Hz) and maintain accuracy down to acquisition times as low as 4 s in length.     

Service Domains for Ambient Services: Concept and Experimentation

We investigate ambient services, which we define as services that are related to the surrounding physical environment of the user, are locally useful and can be considered a form of location-based services. We introduce the notion of service domain which refers to the geographical area of relevance and utility for ambient services. We also consider a stereotypical case where a user might be within multiple service domains at the same time (when the service domains containing the user overlap) and so, can utilize a collection of services comprising services selected from each of the service domains containing the user. A language of operators is given for defining such a collection of services in terms of constituent services from the overlapping service-domains. Moreover, we describe and evaluate a prototype system that shows how to compute the services for a user in multiple service domains. The result is a framework for reasoning about ambient services for filtering or proactively suggesting mobile services based on geographical boundaries. Seng Wai Loke is a Faculty of Information Technology Research Fellow at Monash University. He is author and co-author of more than 90 research papers published in journals, books, conferences, and workshops. His research interests are intelligent and mobile agents, service-oriented computing, and pervasive computing including device ecologies, context-aware systems, mobile services, and ubiquitous e-commerce. He has been on the program committee of more than ten conferences and workshops in the area of mobile computing and agents. Shonali Krishnaswamy received a PhD in Computer Science from Monash University (Australia) in 2003. She currently holds the position of a Research Fellow in the School of Computer Science and Software Engineering at Monash University. Her research interests include Service Oriented Systems, Software Agents and Distributed/Ubiquitous Data Mining. She is a member of ACM and IEEE Computer Societies. Thin Thin Naing has completed her Masters by Information Technology (MIT by Minor Thesis) from the School of Computer Science and Software Engineering at Monash University, Australia. Her research interests include Mobile Services, Location-based Services and Ambient services.This revised version was published online in August 2005 with a corrected cover date.     

Detection of Modulated Gaussian Signals in Noise

A method using Hermite polynomials is utilized for analyzing the outputs of νth-law devices for inputs of modulated Gaussian signals and zero-mean Gaussian noise. New results are developed for the output correlation functions, and techniques for obtaining closed-form expressions are pointed out. Output signal-to-noise ratios for various input carrier-to-noise-power ratios are calculated, and plots are shown for a single sinusoidal modulating signal. Results are derived to show the existence of a theoretical maximum for the output signal-to-noise ratio. The method can be directly applied for the case of general Fourier expandable signals modulating a Gaussian carrier.     

Triangular‐shaped super‐thin microwave network cloak in antenna applications

In this research article, a triangular‐shaped microwave network cloak made out of interconnected patches was designed at the frequency of 2.88 GHz. Its performances in terms of field distributions and radar cross section scattering were compared with the existing structures. The novel triangular‐shaped cloak structure was then applied to cloak a hindering obstacle placed in front of an electromagnetic source. The simulated scattering parameter and radiation pattern of antenna source were then validated through the experimental results. Also, the proposed structure was applied to reduce the mutual interference between two neighboring antennas. The effects of various parameters such as position and size of the cloak, dielectric constant, and substrate thickness on the cloaking effect were also simulated and studied.     

Folding at the Microscale: Enabling Multifunctional 3D Origami‐Architected Metamaterials

Mechanical metamaterials inspired by the Japanese art of paper folding have gained considerable attention because of their potential to yield deployable and highly tunable assemblies. The inherent foldability of origami structures enlarges the material design space with remarkable properties such as auxeticity and high deformation recoverability and deployability, the latter being key in applications where spatial constraints are pivotal. This work integrates the results of the design, 3D direct laser writing fabrication, and in situ scanning electron microscopic mechanical characterization of microscale origami metamaterials, based on the multimodal assembly of Miura‐Ori tubes. The origami‐architected metamaterials, achieved by means of microfabrication, display remarkable mechanical properties: stiffness and Poisson’s ratio tunable anisotropy, large degree of shape recoverability, multistability, and even reversible auxeticity whereby the metamaterial switches Poisson’s ratio sign during deformation. The findings here reported underscore the scalable and multifunctional nature of origami designs, and pave the way toward harnessing the power of origami engineering at small scales.     

Intelligent Biomedical Electrocardiogram Signal Processing for Cardiovascular Disease Diagnosis

Automatic biomedical signal recognition is an important process for several disease diagnoses. Particularly, Electrocardiogram (ECG) is commonly used to identify cardiovascular diseases. The professionals can determine the existence of cardiovascular diseases using the morphological patterns of the ECG signals. In order to raise the diagnostic accuracy and reduce the diagnostic time, automated computer aided diagnosis model is necessary. With the advancements of artificial intelligence (AI) techniques, large quantity of biomedical datasets can be easily examined for decision making. In this aspect, this paper presents an intelligent biomedical ECG signal processing (IBECG-SP) technique for CVD diagnosis. The proposed IBECG-SP technique examines the ECG signals for decision making. In addition, gated recurrent unit (GRU) model is used for the feature extraction of the ECG signals. Moreover, earthworm optimization (EWO) algorithm is utilized to optimally tune the hyperparameters of the GRU model. Lastly, softmax classifier is employed to allot appropriate class labels to the applied ECG signals. For examining the enhanced outcomes of the proposed IBECG-SP technique, an extensive simulation analysis take place on the PTB-XL database. The experimental results portrayed the supremacy of the IBECG-SP technique over the recent state of art techniques.