scholarly journals A Microtester for Measuring the Reliability of Microdevices in Controlled Environmental Conditions

Micromachines ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 585
Author(s):  
Yunjia Li ◽  
Weitao Dou ◽  
Chenyuan Zhou ◽  
Xinyi Wang ◽  
Aijun Yang ◽  
...  

A miniaturized reliability test system for microdevices with controlled environmental parameters is presented. The system is capable of measuring key electrical parameters of the microdevices while controlling the environmental conditions around the microdevices. The test system is compact and thus can be integrated with standard test equipment for microdevices. By using a feed-forward decoupling algorithm, the presented test system is capable of generating a temperature range of 0–120 °C and a humidity range of 20–90% RH (0–55 °C), within a small footprint and weight. The accuracy for temperature and humidity control is ±0.1 °C and ±1% RH (30 °C), respectively. The functionality of the proposed test system is verified by integrating it with a piezo shaker to test the environmental reliability of an electromagnetic vibration energy harvester. The proposed system can be used as a proof-of-technology platform for characterizing the performance of microdevices with controlled environmental parameters.

2011 ◽  
Vol 367 ◽  
pp. 507-515
Author(s):  
Tajudeen H. Sikiru ◽  
Olorunfemi Ojo ◽  
Boyi Jimoh

Manufacturers usually specify photovoltaic (PV) modules at standard test conditions of and , which may not be attainable anywhere in the world. Therefore, to determine the performance of PV modules at naturally occurring irradiance and ambient temperature, this paper proposes a theoretical methodology. This method could be used to predict the performance of PV modules given the irradiance and the ambient temperature at the site of installation. A novel technique that is based on the current-voltage characteristic model is used, it accounts for the variability in the environmental parameters. The irradiance and the ambient temperature of Zaria, Nigeria were used as an illustrative example, which showed the effects of the environmental conditions on the performance of PV modules.


Author(s):  
Rasol Murtadha Najah

This article discusses the application of methods to enhance the knowledge of experts to build a decision-making model based on the processing of physical data on the real state of the environment. Environmental parameters determine its ecological state. To carry out research in the field of expert assessment of environmental conditions, the analysis of known works in this field is carried out. The results of the analysis made it possible to justify the relevance of the application of analytical, stochastic models and models based on methods of enhancing the knowledge of experts — experts. It is concluded that the results of using analytical and stochastic objects are inaccurate, due to the complexity and poor mathematical description of the objects. The relevance of developing information support for an expert assessment of environmental conditions is substantiated. The difference of this article is that based on the analysis of the application of expert methods for assessing the state of the environment, a fuzzy logic adoption model and information support for assessing the environmental state of the environment are proposed. The formalization of the parameters of decision-making models using linguistic and fuzzy variables is considered. The formalization of parameters of decision-making models using linguistic and fuzzy variables was considered. The model’s description of fuzzy inference is given. The use of information support for environment state assessment is shown on the example of experts assessing of the land desertification stage.


2013 ◽  
Vol 592-593 ◽  
pp. 610-613
Author(s):  
Sina Amiri ◽  
Nora Lecis ◽  
Andrea Manes ◽  
Davide Mombelli ◽  
Marco Giglio

Different approaches have been proposed in order to determine the material behavior of ductile materials. Since, the mechanical properties of a mechanical component are modified during manufacturing process due to plastic deformation, heat treatment and etc, a non-destructive indentation experimental procedure addressed to predict the elastic-plastic properties of material after manufacturing process is of interest. This is especially true for small size components where it is complex to extract specimens to test on standard test system. Based on dimensionless analysis and the concept of a representative strain, different approaches have been proposed to determine the material properties of power law materials by using indentation process. In this work, the Johnson-Cook (JC) constitutive model of the aluminum alloy Al6061-T6 is characterized by means of a well-defined optimization procedure based on micro-indentation testing and high fidelity finite element models and an optimization procedure but without the concept of dimensionless analysis and a representative strain. This methodology allows determining a set of JC constants for Al6061-T6. The obtained results have good agreement with parameters calibrated by means of universal standard tests and reverse engineering approach.


2021 ◽  
Author(s):  
Shane C. Miller ◽  
Diana P Baumann ◽  
M. Shane Merryman

The starlet sea anemone (Nematostella vectensis) is an emerging model organism, and we have maintained a colony at the Stowers Institute since 2007. Nematostella are known as a simple sea anemone, related to other cnidarians such as jellyfish and corals. Native to estuarine environments across the Atlantic coast of North America, from Novia Scotia to Florida, they encounter a variety of environmental conditions (e.g., temperature, salinity). Acknowledging that husbandry conditions and environmental parameters can impact research results we provide information about the housing, nutrition, maintenance, and health for our colony of Nematostella. This information will be applicable to any Nematostella housed in the facility in 2021.


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