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The purpose of this paper is to design and develop an instrument for non-destructive fabric grams per square metre (GSM) measurement. This study uses the capacitance principle to obtain the fabric GSM. The relative permittivity of the sample fabrics changes the capacitance value. A relationship between capacitance and GSM that best fits the look-up table is obtained. Also, the developed system is applicable for all kind of fabrics both knitted and woven fabrics. The comparison study was carried out with existing test method.

The purpose of the study is to design and develop an instrument for non-destructive fabric GSM measurement.

The proposed non-destructive method of fabric GSM measurement using capacitance principle is designed, developed and tested. Also, the developed system is applicable for all kind of fabrics both knitted and woven fabrics. The comparison study was carried out with existing test method.

The change in capacitance due to relative permittivity of the sample fabric is in pF range (10-12). The system can be further improved by using a capacitance sensor of sensitivity upto 1 fF (10-15). By doing so, the proposed system provides better results in terms of accuracy and resolution. The system developed can be further extended by making it online equipment which measures the fabric GSM instantaneously.

So far there is no non-destructive testing method available for fabric weight measurement. The newly designed and developed instrument is used to test the fabric both woven and knitted non-destructively.

In this chapter, an attempt has been made to develop a security-based hardware system using an 8-bit single-chip microcontroller in conjunction with some sensor technology and lighting and alarming actuators. The proposed system aims to ensure the security and privacy of a dedicated area in terms of unauthorized human intrusion, hazardous gas leakage, extreme prolonged temperature changes, atypical smoke or vapor content in space and abrupt drop in illumination. The proposed system is capable of detecting any type of physical intervention and hazardous anomalies in the environment of the reserved space. In order to define the operation of the system, programs written in C++ with the special rule of code structuring have been deployed on the microcontroller using the Arduino Integrated Development Environment. The system is like a small container, enclosing all the respective sensor modules, microcontroller board and open connections for actuators. The proposed system is easy to use hardware and does not demand any human intervention for its functioning and can be installed with almost no changes in the infrastructure.

These implementations not only generate excessive voltage levels to enhance the quality of power but also include a detailed investigating of the various modulation methods and control schemes for multilevel inverter (MLI) topologies. Reduced harmonic modulation technology is used to produce 11-level output voltage with the production of renewable energy applications. The simulation is done in the MATLAB/Simulink for 11-level symmetric MLI and is correlated with the conventional inverter design.

This paper is focused on investigating the different types of asymmetric, symmetric and hybrid topologies and control methods used for the modular multilevel inverter (MMI) operation. Classical MLI configurations are affected by performance issues such as poor power quality, uneconomic structure and low efficiency.

The variations in both carrier and reference signals and their performance are analyzed for the proposed inverter topologies. The simulation result compares unipolar and bipolar pulse-width modulation (PWM) techniques with total harmonic distortion (THD) results. The solar-fed 11-level MMI is controlled using various modulation strategies, which are connected to marine emergency lighting loads. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by using SPARTAN 3A field programmable gate array (FPGA) board and the least harmonics are obtained by improving the power quality.

The simulation result compares unipolar and bipolar PWM techniques with THD results. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by a SPARTAN 3A field programmable gate array (FPGA) board, and the power quality is improved to achieve the lowest harmonics possible.

IEEE 802.15.4 is a new standard uniquely designed for low‐rate wireless sensor networks (WSNs). It targets low data rate, low power consumption and low‐cost wireless networking, and offers device level wireless connectivity. The purpose of this paper is to propose a traffic adaptive power control algorithm for beacon relayed distributed WSNs.

A general coordinated sleeping algorithm and the traffic adaptive algorithm are combined in an IEEE 802.15.4 MAC protocol to achieve high‐energy efficiency and high performance at the same time.

By observing the sporadic traffic and beacon relaying characteristics of WSNs, the paper proposes a traffic‐adaptive IEEE 802.15.4 MAC with a coordinated sleeping algorithm. Based on various performance studies, it was found that the proposed algorithm can significantly improve power consumptions in wireless sensor networks.

The paper is of value in proposing a traffic adaptive power control algorithm showing highly efficient power consumptions in low‐traffic conditions as well as with an acceptable degree of adaptation to high‐traffic conditions. In delay performance, it shows longer delay performance compared with other schemes because of the beacon relay procedure while the proposed algorithm reduces the power consumptions dramatically.

Data integration is to combine data residing at different sources and to provide the users with a unified interface of these data. An important issue on data integration is the existence of conflicts among the different data sources. Data sources may conflict with each other at data level, which is defined as data inconsistency. The purpose of this paper is to aim at this problem and propose a solution for data inconsistency in data integration.

A relational data model extended with data source quality criteria is first defined. Then based on the proposed data model, a data inconsistency solution strategy is provided. To accomplish the strategy, fuzzy multi-attribute decision-making (MADM) approach based on data source quality criteria is applied to obtain the results. Finally, users feedbacks strategies are proposed to optimize the result of fuzzy MADM approach as the final data inconsistent solution.

To evaluate the proposed method, the data obtained from the sensors are extracted. Some experiments are designed and performed to explain the effectiveness of the proposed strategy. The results substantiate that the solution has a better performance than the other methods on correctness, time cost and stability indicators.

Since the inconsistent data collected from the sensors are pervasive, the proposed method can solve this problem and correct the wrong choice to some extent.

In this paper, for the first time the authors study the effect of users feedbacks on integration results aiming at the inconsistent data.

Visually impaired people have long been living in the dark. They cannot realize the colorful world with their vision, so they rely on hearing, touch and smell to feel the space they live in. Lacking image information, they face challenges in the external environment and barrier spaces. They face danger that is hundreds of times higher than that faced by normal people. Especially during outdoor activities, they can only explore the surrounding environment aided by their hearing and crutches and then based on a vague impression speculate where they are located. To let the blind confidently take each step, this paper proposes sticking the electronic tag of the radio-frequency identification (RFID) system on the back of guide bricks.

Thus, the RFID reader, ultrasonic sensor and voice chip on a wheeled mobile robot link the front end to the crutch. Once the blind person nears a guide brick, the RFID will read the message on the tag through the voice broadcast system, and a voice will inform the visually impaired person of the direction to walk and information of the surrounding environment. In addition, the CMOS image sensor set up in the wheeled mobile robot is used to detect the black marking on the guide brick and to guide the blind to walk forward or turn around between the two markings. Finally, the lithium battery charging control unit was installed on the wheeled mobile robot. The ATtiny25 microcontroller conducts the battery charge and discharge control and monitoring of the current battery capacity.

The development of this system will let visually impaired people acquire environmental information, road guidance function and nearby traffic information.

Through rich spatial environment messages, the blind can have the confidence and courage to go outside.

The purpose of this paper is to develop a highly miniaturized wireless inertial sensor system based on a novel 3D packaging technique using a flexible printed circuit (FPC). The device is very suitable for wearable applications in which small size and lightweight are required such as body area network, medical, sports and entertainment applications.

Modern wireless inertial measurement units are typically implemented on a rigid 2D printed circuit board (PCB). The design concept presented here is based around the use of a novel planar, six‐faceted, crucifix or cross‐shaped FPC instead of a rigid PCB. A number of specific functional blocks (such as microelectromechanical systems gyroscope and accelerometer sensors, microcontroller (MCU), radio transceiver, antenna, etc.) are first assigned to each of the six faces which are each 1 cm² in area. The FPC cross is then developed into a 1 cm³, 3D configuration by folding the cross at each of five bend planes. The result is a low‐volume and lightweight, 1 cm³ wireless inertial sensor that can sense and send motion sensed data wirelessly to a base station. The wireless sensor device has been designed for low power operation both at the hardware and software levels. At the base station side, a radio receiver is connected to another MCU unit, which sends received data to a personal computer (PC) and graphical user interface. The industrial, scientific and medical band (2.45 GHz) is used to achieve half duplex communication between the two sides.

A complete wireless sensor system has been realized in a 3D cube form factor using an FPC. The packaging technique employed during the work is shown to be efficient in fabricating the final cubic system and resulted in a significant saving in the final size and weight of the system. A number of design issues are identified regarding the use of FPC for implementing the 3D structure and the chosen solutions are shown to be successful in dealing with these issues.

Currently, a limitation of the system is the need for an external battery to power the sensor system. A second phase of development would be required to investigate the possibility of the integration of a battery and charging system within the cube structure. In addition, the use of flexible substrate imposes a number of restrictions in terms of the ease of manufacturability of the final system due to the requirement of the required folding step.

The small size and weight of the developed system is found to be extremely useful in different deployments. It would be useful to further explore the system performance in different application scenarios such as wearable motion tracking applications. In terms of manufacturability, component placement needs to be carefully considered, ensuring that there is sufficient distance between the components, bend planes and board edges and this leads to a slightly reduced usable area on the printed circuit.

This paper provides a novel and useful method for realizing a wireless inertial sensor system in a 3D package. The value of the chosen approach is that a significant reduction in the required system volume is achieved. In particular, a 78.5 per cent saving in volume is obtained in decreasing the module size from a 25 to a 15 mm³ size.