Acetone Sensor Based on FAIMS-MEMS

In this paper, to address the problems of large blood draws, long testing times, and the inability to achieve dynamic detection of invasive testing for diabetes, stemming from the principle that type 1 diabetic patients exhale significantly higher levels of acetone than normal people, a FAIMS-MEMS gas sensor was designed to detect acetone, which utilizes the characteristics of high sensitivity, fast response, and non-invasive operation. It is prepared by MEMS processes, such as photolithography, etching, and sputtering, its specific dimensions are 4000 μm in length, 3000 μm in width and 800 μm in height and the related test system was built to detect acetone gas. The test results show that when acetone below 0.8 ppm is introduced, the voltage value detected by the sensor basically does not change, while when acetone gas exceeds 1.8 ppm, the voltage value detected by the sensor increases significantly. The detection accuracy of the sensor prepared by this method is about 0.02 ppm/mV, and the voltage change can reach 1 V with a response time of 3 s and a recovery time of 4 s when tested under 20 ppm acetone environment; this has good repeatability and stability, and has great prospects in the field of non-invasive detection of type 1 diabetes.

Expected electromagnetic environment at the energy infrastructure facilities of remote ports (berths)

The article deals with the issues of electromagnetic compatibility of coastal and floating objects in the waters of ports (berths). The subject of the study is the processes occurring in the electrical network when powering ships of the technical fleet and floating objects from the shore, which determine the need for automated calculation of conductive low-frequency electromagnetic disturbance for their subsequent suppression. An algorithm for calculating the parameters of the electromagnetic environment is presented, which is based on the analysis of the distribution parameters of slow voltage changes. The mechanism of EMD occurrence in voltage deviation is described and a mathematical model explaining the probability of its occurrence is presented. An algorithm for calculating the parameters of the electromagnetic environment based on slow voltage changes in the network is compiled. This algorithm is implemented in the “Program for the study of slow voltage changes by the load changingof the electrical network ". For the object under study, the parameters of the distribution of conductive low-frequency electromagnetic disturbance over a slow voltage change are determined. A block diagram of an automatic voltage regulator implementing the proposed voltage stabilization law has been developed.

Energy Management Method for Fast-Charging Stations with the Energy Storage System to Alleviate the Voltage Problem of the Observation Node

Large-scale fast charging of electric vehicles (EVs) probably causes voltage deviation problems in the distribution network. Installing energy storage systems (ESSs) in the fast-charging stations (FCSs) and formulating appropriate active power plans for ESSs is an effective way to reduce the local voltage deviation problem. Some deterministic centralized strategies used for ESSs at FCSs are proposed to solve the voltage deviation problem mentioned above. However, the randomness of the EV load is very large, which can probably reduce the effects of deterministic centralized strategies. A fast and reliable centralized strategy considering the randomness of the EV load for ESSs is a key requirement. Therefore, we propose in this paper a day-ahead scheduling strategy with the aim of maximizing the probability of the nodal voltage change being smaller than a preset limit at the observation node. In the proposed strategy, the uncertainty of EV load is taken into account and the probability of the voltage change of an observation node is quantified by a proposed analytic assessment model (AMM). Furthermore, a voltage change optimization model (VCOM) based on a novel control parameter β is proposed, where β can be used as a constraint to suppress the nodal voltage change at the observation node. Finally, the IEEE 33-bus test system is used to verify the effectiveness of the proposed day-ahead ESS strategy.

Modelling of voltage changes in the n-p junction in the pulse mode

The article presents the results of modeling the effect of the effective lifetime in the space charge region (SCR) of the n+-p junction on the impulse characteristics of silicon structures. The model is based on solving the fundamental system of differential equations for the transport of charge carriers in inhomogeneous semiconductors. The calculated time dependences of the voltage change in the SCR for a pulse voltage change on the n+-p-p+ structure correspond to the experimental data.

Quantitative Study of Photoelectric Laser Stimulation for Logic State Imaging in Embedded SRAM

The use of optical techniques for attacking integrated circuits (ICs) at the silicon level is increasingly being reported. Although these attacks can be complex to set and require skilled attacker that can access expensive equipment, they are nonetheless very powerful. Among the different applications described in literature, there has been a focus on extracting data directly from embedded SRAM. Such attacks can provide access to highly sensitive information such as encryption keys and bypass various security strategies. An attacker usually exploits one of the several interactions that exist between light and semiconductor to generate an image where content can be directly qualified by the data in memory (Logic State Image – LSI). Thermal laser stimulation (TLS) and laser probing (EOFM-Electro-Optical Frequency Mapping) have been reported in the literature recently but Photoelectric Laser Stimulation (PLS) did not get as much attention. Considering the potential advantages of PLS over other techniques (e.g. lower power requirements to generate current/voltage change, effect can be triggered at shorter wavelength which may lead to an improved spatial resolution), we investigate in this paper if logic state images can be generated with PLS on a variety of devices and do a comparative assessment with state-of-the-art technologies to assess potential benefits and limitations.

Single-Ended Fast Protection for Transient Power of Multi-Terminal Flexible and Direct Power Grids Containing Renewable Energy

With the proposal of the carbon peak goal, a multi-terminal flexible DC grid containing various renewable energy becomes the one of main ways of renewable energy power transmission. Thus, it is increasingly important to improve its transmission reliability and stability. This paper proposes a single-ended protection principle based on the analysis method of transient power change for the “mesh structure” ring-shaped flexible direct current (DC) grid. Based on the propagation characteristics of voltage, current, and anti-traveling waves during fault periods, the transient power variation coefficient based on SOD transformation is introduced to distinguish the internal and external faults. Besides, simulation based on the PSCAD/EMTDC platform within the Zhangbei four-port network verifies the effectiveness of the proposed protection principle under various fault conditions. Meanwhile, the protection criterion is designed according to the difference in the change coefficient of the transient power SOD within and outside the fault time zone. Moreover, the setting value of the start of protection is obtained by analyzing the simulation results, thus a set of fast and reliable single-ended protections for the same-side short-time transient power window of an enhanced flexible straight power grid is developed via combining it with the starting criterion of a sudden voltage change.

Hydrogen-Terminated Diamond Surface as a Gas Sensor: A Comparative Study of Its Sensitivities

A nanocrystalline diamond (NCD) layer is used as an active (sensing) part of a conductivity gas sensor. The properties of the sensor with an NCD with H-termination (response and time characteristic of resistance change) are measured by the same equipment with a similar setup and compared with commercial sensors, a conductivity sensor with a metal oxide (MOX) active material (resistance change), and an infrared pyroelectric sensor (output voltage change) in this study. The deposited layer structure is characterized and analyzed by Scanning Electron Microscopy (SEM) and Raman spectroscopy. Electrical properties (resistance change for conductivity sensors and output voltage change for the IR pyroelectric sensor) are examined for two types of gases, oxidizing (NO2) and reducing (NH3). The parameters of the tested sensors are compared and critically evaluated. Subsequently, differences in the gas sensing principles of these conductivity sensors, namely H-terminated NCD and SnO2, are described.