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This paper aims to study a power management circuit for a piezoelectric vibration energy harvester. It presents how to accumulate energy and provide regulated DC voltage for practical applications.

Energy storage and extraction circuit are proposed. While the storage stage consists of a full wave rectifier and a storage capacitor, the extraction stage includes a voltage comparator and regulator, which may provide the load steady DC voltage when the voltage of the storage capacitor is higher than the threshold.

The numerical analysis and experimental results indicate that it takes a longer time to charge to a specified voltage for the greater storage capacitor and the net charge flowing into the storage capacitor during each period decreases when the voltage of the storage capacitor is higher. The higher threshold voltage of the capacitor has lower harvesting efficiency owing to the rate of charging of the storage capacitor slowing down over time.

Because of the chosen research method, the power management circuit is only suitable for the piezoelectric vibration energy harvester under resonant conditions.

This study includes practically useful applications for users to build a power management circuit for piezoelectric energy harvester.

This study presents results that the charging efficiency of the storage circuit is relative to the storage capacitor and the threshold voltage.

Fully automating the apparel assembly process will require generic robotic manipulators which can be purchased as a complete unit and adapted to specific applications. A manipulator that can handle and position non‐rigid fabric parts of inexact dimension is described. The XY‐theta provides three directions of fabric positioning. Further, the manipulator can handle different sizes of a variety of styles. The aligning system is composed of three modules‐ vision, positioning and control, which exchange information and control signals via a 32‐bit bus system. This combination of modules and bus system makes the aligning system very flexible which is represented by the ability to switch the type of microcontroller or motors used. Thus, the generic system can be adapted for specific applications.

The purpose of this paper is to provide a review of recent developments in electromagnetic radiation (EMR) sensing.

Following a short introduction, this paper discusses a selection of recent research and development activities concerning the sensing of gamma radiation, X‐rays and ultraviolet (UV) radiation.

This shows that novel sensors are being developed for all of these classes of EMR. Improved gamma sensors are attracting strong interest in the USA, reflecting concerns regarding nuclear security. Novel X‐ray and UV sensors are often being developed in response to new and emerging uses of these types of radiation.

This paper provides a technical review of recent research into sensors for detecting gamma radiation, X‐rays and UV radiation.

Existing control circuits for piezoelectric energy harvesting (PEH) suffers from long startup time or high power consumption. This paper aims to design an ultra-low power control circuit that can harvest weak ambient vibrational energy on the order of several microwatts to power heavy loads such as wireless sensors.

A self-powered control circuit is proposed, functioning for very brief periods at the maximum power point, resulting in a low duty cycle. The circuit can start to function at low input power thresholds and can promptly achieve optimal operating conditions when cold-starting. The circuit is designed to be able to operate without stable DC power supply and powered by the piezoelectric transducers.

When using the series-synchronized switch harvesting on inductor circuit with a large 1 mF energy storage capacitor, the proposed circuit can perform 322% better than the standard energy harvesting circuit in terms of energy harvested. This control circuit can also achieve an ultra-low consumption of 0.3 µW, as well as capable of cold-starting with input power as low as 5.78 µW.

The intermittent control strategy proposed in this paper can drastically reduce power consumption of the control circuit. Without dedicated cold-start modules and DC auxiliary supply, the circuit can achieve optimal efficiency within one input cycle, if the input signal is larger than voltage threshold. The proposed control strategy is especially favorable for harvesting energy from natural vibrations and can be a promising solution for other PEH circuits as well.

The paper presents the results of extensive studies on circuit board solderability comparing wetting balance and IPC test methods through performance in vapour phase and wave soldering operations. The effects on solderability of key parameters are examined and compared with storage times of one year, and accelerated ageing using damp heat, dry heat and steam oxygen. An evaluation is made of tin‐lead alloys from 40/60 to 70/30 in solder coating thicknesses from 0·1 to 1·0 mil.

To meet the ever increasing quality standard set by the manufacturers of multilayer printed circuit boards, IMASA, in association with Enthone Inc. USA, has further developed the Enplate MLB permanganate etch back system to improve the hole quality of a multilayer printed circuit board. To enable manufacturers to utilise this improvement using existing equipment, Short Line Chemistry was developed.

The purpose of this paper is to design a low power clock gating technique using Galeor approach by assimilated with replica path pulse triggered flip flop (RP-PTFF).

In the present scenario, the inclination of battery for portable devices has been increasing tremendously. Therefore, battery life has become an essential element for portable devices. To increase the battery life of portable devices such as communication devices, these have to be made with low power requirements. Hence, power consumption is one of the main issues in CMOS design. To reap a low-power battery with optimum delay constraints, a new methodology is proposed by using the advantages of a low leakage GALEOR approach. By integrating the proposed GALEOR technique with conventional PTFFs, a reduction in power consumption is achieved.

The design was implemented in mentor graphics EDA tools with 130 nm technology, and the proposed technique is compared with existing conventional PTFFs in terms of power consumption. The average power consumed by the proposed technique (RP-PTFF clock gating with the GALEOR technique) is reduced to 47 per cent compared to conventional PTFF for 100 per cent switching activity.

The study demonstrates that RP-PTFF with clock gating using the GALEOR approach is a design that is superior to the conventional PTFFs.

The driving forces behind recent significant improvements in organic packages for microelectronic applications are electrical performance, product weight, size and manufacturing cost. A very careful selection of optimum manufacturing processes, equipment and materials, and stringent control of critical manufacturing operations are prerequisites for success in this emerging market place. Major technical and business related challenges to a printed circuit board manufacturer who plans to enter this market are discussed.

Higher densities and concerns for human health are driving the need for better EMC protection on PCBs in automotive applications. Simultaneously, there is a strong need to reduce circuit costs. Ford, Circuit Wise and Du Pont have worked together to develop the use of polymer thick film (PTF) conductors to provide EMC protection in automotive circuits at a fraction of the cost of adding additional conventional ground plane layers. This paper will discuss the reliability and electrical performance of this approach. The PTF approach is fully compatible with conventional PCB fabrication and assembly processes, including hot air solder levelling and surface‐mounting, and gives EMC protection comparable to or better than that of additional copper ground planes.

To improve the voltage quality in AC adjustable high-power-speed-drive applications, the purpose of the paper is to provide a large number of output levels without increasing the number of commutation cells in the three-phase, n-cells flying capacitor voltage source asymmetric Multilevel Inverter (MI). The concept is based on the selection of different ratios between the breakdown voltages of two successive power devices. The new mathematical model is developed under various ratios, allows a thorough investigation of the harmonic distortions, flying capacitor energy storage, flying capacitor voltage balancing controllability and blocking voltage insulated gate bipolar transistor (IGBT) capability.

The asymmetrical design provides a large number of output levels without increasing the number of commutation cells. The important new analytical expression of capacitors voltage distribution is derived and extended to any ratio between the switch breakdown voltages of two successive power devices.

The detailed simulation study of the proposed concept has been carried out using MATLAB/Simulink. The power switches control of the three-phase three-cell MI is assured by new phase-shifted-multi-carrier pulse width modulation. The space vector representation is used to show the regular and irregular step output voltage in the complex plan (α,β).

In the paper, the n cells flying capacitor inverter, which typically operates in the (n + 1) levels mode, was extended to (n + 2), (n + 3) … until 2ⁿ levels with regular or irregular step output voltage. Consequently, the claimed advantages of the asymmetric MI are to improve power quality by reducing harmonic distortions and to reduce the requirement on capacitive energy storage in the circuit.