This paper presents a novel technique for sensing direction, angle and velocity from rotation of shafts using simple Shape Memory Alloy (SMA) based micro-switches. Due to electro-mechanical coupling of SMA wires reflected in controlled force generation capacity, the SMA based devices can provide better alternatives for traditional relays, solenoid valves and opto-coupler isolators. The control algorithm involved in this sensing technique, reads the switch status for shaft rotation and sense the angular displacement thereafter. One of the advantages, this new sensor offers is its inherent robustness to vibration in the host platform. Experiments are carried out under vibrating conditions and obtained results are compared with conventional optical incremental encoder. The result shows that SMA based angle encoder works efficiently and gives more accurate results under disturbance while optical encoders are quite sensitive to similar platform vibration. Due to its compactness and lightweight, this concept of SMA wire based angle sensor is envisaged to be suitable for structural health monitoring applications where discrete angle information is needed at low RPM. Copyright © 2011 IFSA.

Un ni iv ve er rs si it tá á d di i B Br re es sc ci ia a, , I It ta aly Sensors & Transducers Journal (ISSN 1726-5479) is a peer review international journal published monthly online by International Frequency Sensor Association (IFSA). Available in electronic and CD-ROM. S Se en ns so or rs s & & T Tr ra an ns sd du uc ce er rs s J Jo ou ur rn na al l C C o o n n t t e e n n t t s s Authors are encouraged to submit article in MS Word (doc) and Acrobat (pdf) formats by Abstract: A single PID controller in a process control loop may suffer from high frequency oscillations without offset or low frequency oscillation with offset. An inverse derivative control action can eliminate both of these errors. In the present paper, a low cost operational amplifier based PID controller with inverse derivative control action has been described. Its transfer function has been derived and is found to be identical with the form already derived by other workers. It has been tested with a process plant analogue and implemented in the voltage control system of a DC generator. Its transfer function along with its characteristics in a process plant analogue and the load characteristics of DC generator with and without this controller have been determined experimentally and reported in this paper.

Un ni iv ve er rs si it tá á d di i B Br re es sc ci ia a, , I It ta aly Sensors & Transducers Journal (ISSN 1726-5479) is a peer review international journal published monthly online by International Frequency Sensor Association (IFSA). Available in electronic and CD-ROM. S Se en ns so or rs s & & T Tr ra an ns sd du uc ce er rs s J Jo ou ur rn na al l C C o o n n t t e e n n t t s s Authors are encouraged to submit article in MS Word (doc) and Acrobat (pdf) formats by Abstract: Ceramic based thin film sensors are well known for gas sensing applications. These sensors are operated at elevated temperature for good sensitivity. ZnO thin film sensors operated at high temperature are used in ammonia sensing application. But to the best of author's knowledge no room temperature ZnO (Zinc Oxide) thin film sensors are reported. The deposited ZnO films are found to be highly unstable with respect to resistance of the films at room temperature. To increase the stability two different techniques viz. annealing and irradiation are tried. Comparative study of annealed and irradiated ZnO films for stability in resistance is done. Further the performance of these films as ammonia (NH 3) gas sensor at room temperature has been studied. The results obtained are reported in this paper and analyzed.

Un ni iv ve er rs si it tá á d di i B Br re es sc ci ia a, , I It ta aly Sensors & Transducers Journal (ISSN 1726-5479) is a peer review international journal published monthly online by International Frequency Sensor Association (IFSA). Available in electronic and CD-ROM. S Se en ns so or rs s & & T Tr ra an ns sd du uc ce er rs s J Jo ou ur rn na al l C C o o n n t t e e n n t t s s Authors are encouraged to submit article in MS Word (doc) and Acrobat (pdf) formats by Abstract: A novel model-based nonlinear control strategy is proposed using an experimental pH neutralization process. The control strategy involves a non linear neural network (NN) model, in the context of internal model control (IMC). When integrated into the internal model control scheme, the resulting controller is shown to have favorable practical implications as well as superior performance. The designed model based online IMC controller was implemented to a laboratory scaled pH process in real time using dSPACE 1104 interface card. The responses of pH and acid flow rate shows good tracking for both the set point and load chances over the entire nonlinear region.

Sensors & Transducers Journal (ISSN 1726-5479) is a peer review international journal published monthly online by International Frequency Sensor Association (IFSA). Available in electronic and CD-ROM. S Se en ns so or rs s & & T Tr ra an ns sd du uc ce er rs s J Jo ou ur rn na al l C C o o n n t t e e n n t t s s I In nf fl lu ue en nc ce e o of f L Li iq qu ui id d P Pe et tr ro ol le eu um m G Ga as s o on n t th he e E El le ec ct tr ri ic ca al l P Pa ar ra am me et te er rs s o of f t th he e W WO O3 3 T Th hi ic ck k F Fi il lm m Authors are encouraged to submit article in MS Word (doc) and Acrobat (pdf) formats by Abstract: Strontium(II)-added ZnAl 2 O 4 composites prepared by sol-gel technique were tested for the detection of acetone vapors. XRD, SEM and BET surface area measurements were employed to identify the structural phases and surface morphology of the composites. The composites were prepared with the molar ratios of Zn: Sr as (1. the aluminium molar ratio as constant for all the compositions and were labeled as ZnSA1, ZnSA2, ZnSA3, ZnSA4, ZnSA5 and ZnSA6 respectively. The samples sintered at 900 o C for 5 h were subjected to dc resistance measurements from room temperature to 200 o C to study the acetone vapor detection characteristics. The results revealed that the sensitivity (S f) increased from room temperature to 150 o C and thereafter decreased. The sensitivity increased with acetone concentration from 100-5000 ppm at an optimum temperature of 150 o C. The composite with higher Sr(II) content on ZnAl 2 O 4 matrix (ZnSA5) showed the best sensitivity to acetone detection.

Un ni iv ve er rs si it tá á d di i B Br re es sc ci ia a, , I It ta aly Sensors & Transducers Journal (ISSN 1726-5479) is a peer review international journal published monthly online by International Frequency Sensor Association (IFSA). Available in electronic and CD-ROM. S Se en ns so or rs s & & T Tr ra an ns sd du uc ce er rs s J Jo ou ur rn na al l C C o o n n t t e e n n t t s s Authors are encouraged to submit article in MS Word (doc) and Acrobat (pdf) formats by Abstract: Regardless of the application domain and deployment scope, the ability to retrieve information is critical to the successful functioning of any wireless sensor network (WSN) system. In general, information extraction procedures can be categorized into three main approaches: agent-based, query-based and macroprogramming. Whilst query-based systems are the most popular, macroprogramming techniques provide a more general-purpose approach to distributed computation. Finally, the agent-based approaches tailor the information extraction mechanism to the type of information needed and the configuration of the network it needs to be extracted from. This suite of three papers (Part I-III) offers an extensive survey of the literature in the area of WSN information extraction, covering in Part I and Part II the three main approaches above. Part III highlights the open research questions and issues faced by deployable WSN system designers and discusses the potential benefits of both in-network processing and complex querying for large scale wireless informational systems.