Aerospace series. Paints and varnishes. Test method for measurement of resistance to cold crack temperature cycle

2015 ◽  
Keyword(s):  
Test Method ◽  
Temperature Cycle

scholarly journals Research on comprehensive load vibration test of electric vehicle motor controller unit

2021 ◽  
Vol 260 ◽  
pp. 03002
Author(s):  
Zhibiao Yan ◽  
Lingxiao Zhao ◽  
Huansheng Ma
Keyword(s):  
Electric Vehicle ◽  
Control Unit ◽  
Test Methods ◽  
Current Data ◽  
Test Method ◽  
Temperature Cycle ◽  
Vibration Test ◽  
Environmental Load ◽  
Electrical Load ◽  
Motor Controller

In this article, the vibration test standards and general test methods for electric vehicle motor control unit are introduced. New vibration test conditions are proposed based on the vibration data collected during the actual vehicle test. Using the vehicle output current data as the electrical load of the motor controller unit, and the temperature cycle as the environmental load, a comprehensive load vibration test method that integrates the electrical load and the environmental load is proposed. According to the test method, the equipment and test process of the comprehensive on-load vibration test of environmental load are determined. Summarized three important principles in the design of fixtures: lightweight, low damping, and no resonance. A novel testing method for motor controllers is proposed.

Transient Thermal Analysis as a Test Method for the Reliability Investigation of High Power LEDs during Temperature Cycle Tests

2013 ◽  
Vol 2013 (1) ◽  
pp. 000902-000907
Author(s):  
Gordon Elger ◽  
Shri Vishnu Kandaswamy ◽  
Robert Derix ◽  
Jürgen Wilde
Keyword(s):  
Thermal Analysis ◽  
Solder Joint ◽  
High Power ◽  
Test Method ◽  
Temperature Cycle ◽  
Electric Resistance ◽  
Transient Thermal Analysis ◽  
Open Contact ◽  
Long Lifetime ◽  
Transient Thermal

Light emitting diodes (LEDs) are today standard and mature light sources. They have several key advantages, like small size, low energy consumption and long lifetime. However, high reliability of the LED system is required to achieve long lifetime of the light source. Thermo-mechanical stress due to temperature cycle causes failure of electronic systems. The electronic component itself or the interconnect device, e.g. printed circuit board (PCB) might fail. In many cases, the weakest link is found to be the solder interconnect between package and the board. Cracking of the interconnect causes an open contact and the system fails. In this paper we compare the existing methods to investigate LED interconnect failures during temperature cycle tests like the simple “light-on-test”, electric resistance measurement and the shear test. We describe and introduce the transient thermal analysis as a measurement method. We present the first reliability data analysis with transient thermal analysis of ceramic high power LED packages on Al-IMS during air to air thermal shock test (−40°C to +125°C) and correlate it with cross sections. We demonstrate the sensitivity of the thermal analysis to detect solder joint failures of the assembly. We compare the results with electric resistance measurements and light on tests and show that the resolution is significantly higher compared to the methods applied today. The sensitivity of the method enables us to detect the crack in a solder joint much earlier than the final failure of the joint, i.e. the open contact.

Metrological support of individual blood glucose meters in telemedicine

2019 ◽  
pp. 52-56
Author(s):  
Yu.F. Glukhov ◽  
N.V. Krutikov ◽  
A.V. Ivanov ◽  
N.P. Muravskaya
Keyword(s):  
Blood Glucose ◽  
Blood Glucose Level ◽  
Glucose Level ◽  
Measurement Data ◽  
Test Method ◽  
Level Measurement ◽  
Measurement Devices ◽  
Real Practice ◽  
Health Care Centers ◽  
Medical Measurement

We have studied and analyzed status and metrological supervision of blood glucose monitors, individual devices for a person’s blood glucose level measurement. It has been indicated that nowadays blood glucose monitors like other individual devices for medical measurement are not allowed to be involved in telemedicine public service. This accounts for absence of metrological supervision with these measurement devices in telemedicine. In addition, the key problem is absence of safe methods and means of remote verificaition, calibration and transmission of measurement data to health care centers. The article offers a remote test method for blood glucose monitors using a number of resistors with values correlating with measured blood glucose level. The available method has been successfully trialed in real practice.

Customer’s satisfaction on service quality at Vietnam Technological and Commercial Joint Stock Bank – An Giang Branch

2020 ◽  
Vol 4 (3) ◽  
pp. First
Author(s):  
Tran Minh Hieu ◽  
Nguyen Duong Ngoc Mai Chi
Keyword(s):  
Customer Satisfaction ◽  
Service Quality ◽  
Test Method ◽  
Quality Of Services ◽  
Factors Affecting ◽  
Factors Influencing ◽  
Alpha Reliability ◽  
Survey Results ◽  
Development Orientation

This study applied SERVQUAL scale of Parasuraman et al to measure factors affecting customer satisfaction on service quality at Vietnam Technological and Commercial Joint Stock Bank - An Giang Branch (Techcombank An Giang). The study was conducted to survey 207 customers who have been using the service at Techcombank An Giang. The survey results were analyzed by the Cronbach's Alpha reliability test method, then used Exploratory factor analysis (EFA) to verify and evaluate the scale of service quality. The results of the regression analysis show that customer's satisfaction about service quality at Techcombank An Giang includes four factors: The factor with the highest level is the Empathy with Beta = 0.253, the second of factor is the Responsibility with Beta = 0.248, ranked third in the influence level is the Tangible with Beta = 0.235, and the lowest impact level is the Reliability with Beta = 0.144. The research also uses statistical methods to describe and test the differences of demographic factors with customer's satisfactionon service quality.The analysis results show that there is no difference between customer's satisfaction on service quality and factors such as gender, age, income, number of transaction banks, regular transaction banks, and time to use the service at Techcombank An Giang. Through the research results, the author would like to propose some ideas to improve the quality of services, thereby attracting new customers and importantly, keeping traditional customers because the development orientation of Techcombank is to take care of old customers to cross sell other products of the bank. The Stud results offer a basis for the branch to identify the factors influencing customer satisfaction on their service quality, thereby having an appropriate strategy to improve customer satisfaction.

An evaluation of ECT sample height for small flute board grades and Box Manufacturer’s Certification compliance

TAPPI Journal ◽  
2009 ◽  
Vol 8 (6) ◽  
pp. 24-28
Author(s):  
CORY JAY WILSON ◽  
BENJAMIN FRANK
Keyword(s):  
Compressive Strength ◽  
Compressive Load ◽  
Test Sample ◽  
Test Methods ◽  
Test Method ◽  
Initial Development ◽  
Sample Height ◽  
Relationship Of ◽  
The Relationship ◽  
Corrugated Fiberboard

TAPPI test T811 is the specified method to ascertain ECT relative to box manufacturer’s certification compliance of corrugated fiberboard under Rule 41/ Alternate Item 222. T811 test sample heights were derived from typical board constructions at the time of the test method’s initial development. New, smaller flute sizes have since been developed, and the use of lighter weight boards has become more common. The T811 test method includes sample specifications for typical A-flute, B-flute, and C-flute singlewall (and doublewall and triplewall) structures, but not for newer thinner E-flute or F-flute structures. This research explores the relationship of ECT sample height to measured compressive load, in an effort to determine valid E-flute and F-flute ECT sample heights for use with the T811 method. Through this process, it identifies challenges present in our use of current ECT test methods as a measure of intrinsic compressive strength for smaller flute structures. The data does not support the use of TAPPI T 811 for ECT measurement for E and F flute structures, and demonstrates inconsistencies with current height specifi-cations for some lightweight B flute.

Evaluating hardness and the S-test

TAPPI Journal ◽  
2019 ◽  
Vol 18 (3) ◽  
pp. 161-169
Author(s):  
Doug Cash ◽  
Benjamin Frank
Keyword(s):  
North American ◽  
Test Method ◽  
Load Curve ◽  
Permanent Damage ◽  
Additional Load ◽  
The North ◽  
Complete Failure

The corrugated industry typically quantifies crush resistance using the Concora corrugated medium test (CMT) on fluted medium or flat crush on combined board. These tests compress the materials until the point of complete failure of the flutes. Combined board elastically resists crushing forces until a certain point, the hardness of the structure, while additional load causes permanent damage and deformation. This study investigates how hardness can be measured directly from a load curve collected during CMT (or flat crush) testing and how it varies throughout the North American paper supply. It also explores how hardness correlates with the values obtained from the newly developed S-test. This new test method deserves further study as a potentially more appropriate specification for crush resistance of corrugated medium.

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