Self-test Function Research Articles

Fiber optics vibration sensor with selftest functionality

Fiber optics vibration sensor with selftest functionality

Proposed Changes to the Inspection Strategy for Fire Alarm Systems: Empirical Analysis of Weak Points and Technical Influencing Factors

Fire alarm systems are an important part of the safety concept in complex buildings. For this reason, there are high availability requirements for the systems, which must be sustained by a maintenance concept. A shortage of skilled workers and rising costs in the construction and operation of buildings are pushing these concepts ever further. This study deals with proposed changes to the maintenance strategies to achieve cost and time savings in addition to an improvement in quality. As a first part of the work, the current state of research on developments in fire alarm systems and their maintenance and inspection concepts is analyzed within a literature review. The results serve as a basis for further research, which is based on a qualitative content analysis of expert interviews and standardized surveys to identify the weaknesses in current inspection strategies and future factors influencing the methods and technology of inspections through technical innovations. As a data basis for this study, expert interviews were conducted with experts from manufacturers, industry associations, and standards bodies in order to determine the possible influencing factors. To determine their relevance for the inspection, more than 40 experts were surveyed about testing the systems. The presented results show that new technical risks, such as cyber threats and networked plant structures, are insufficiently covered by current inspection strategies. Furthermore, inspection steps can be substituted by new technologies. The most important influencing factors that can be identified here are automatic self-test functions of components and remote inspection techniques of the systems. Finally, the results are discussed within the framework of a PESTEL analysis. In conclusion, it can be stated that the integration of identified impacts in future inspection strategies brings time and efficiency benefits in the operation of systems.

Patient Self-Testing of Kidney Function at Home, a Prospective Clinical Feasibility Study in Kidney Transplant Recipients

People with long-term health conditions often attend clinics for kidney function tests. The Self-Testing Own Kidneys (STOK) study assessed feasibility of kidney transplant recipients using hand-held devices to self-test kidney function at home and investigated agreement between home self-test and standard clinic test results. A prospective, observational, single-center, clinical feasibility study (TRN: ISRCTN68116915), with N= 15 stable kidney transplant recipients, investigated blood potassium and creatinine results agreement between index self-tests at home (patient self-testing of capillary blood, using Abbott i-STAT Alinity analyzers [i-STAT]) and reference tests in clinic (staff sampled venous blood, analyzed with laboratory Siemens Advia Chemistry XPT analyzer) using Bland-Altman and error grid analysis. The mean within-patient difference between index and reference test in creatinine was 2.25 μmol/l (95% confidence interval [CI]:-12.13, 16.81 μmol/l) and in potassium was 0.66 mmol/l (95% CI:-1.47, 2.79 mmol/l). All creatinine pairs and 27 of 40 (67.5%) potassium pairs were judged clinically equivalent. Planned follow-up analysis suggests that biochemical variables associated with potassium measurement in capillary blood were predominant sources of paired test result differences. Paired patient and nurse i-STAT capillary blood test potassium results were not statistically significantly different. This small feasibility study observed that training selected patients to competently use hand-held devices to self-test kidney function at home is possible. Self-test creatinine results showed good analytical and clinical agreement with standard clinic test results. Self-test potassium results showed poorer agreement with standard clinic test results; however, patient self-use of i-STATs at home was not a statistically significant source of difference between paired potassium test results.

Design and Development of a Data Structure Visualisation System Using the Ant Colony Algorithm

Aim: A data structure visualisation system uses object-oriented thinking and COM technology to dynamically and interactively simulate and track data structure algorithms and realize the dynamic synchronisation and visualisation of abstract data structures and algorithms using the data modelling function and self-test function. Background: Teaching data structures and algorithms is difficult because of their abstraction and dynamics; the use of icons in classroom teaching can be partially abstracted into intuition, but analysing the instantaneous dynamic characteristics of the object and the dynamic execution process of the algorithm is difficult. Objective: A data structure visualisation system employs a data modelling function, visual data structures, a user-friendly and flexible interface, and multipath features for multilevel users. Such systems can be designed more effectively by using the ant colony algorithm. Methods: The more the ants pass by a certain path, the higher the concentration of residual pheromone, and the higher the probability of the subsequent ant selecting that path. Therefore, the individuals in an ant colony communicate messages and cooperate with each other for foraging. Results: The resulting speedup ratio indicates that the speedup is smaller when the number of nodes is 100 or more; the acceleration is higher when the node reaches a certain scale, and the speedup ratio does not change considerably. In this study, the traffic simulation software VISSIM was used to generate road network data; the generated traffic data were analysed and used to design a traffic network data structure. Conclusion: The traffic network data model oriented to the ant colony algorithm was established through abstraction. Accordingly, a parallel ant colony algorithm based on cloud computing was implemented. Finally, a Hadoop cloud computing platform was established and used to run and test the parallel ant colony algorithm program; several experiments were conducted, and the experimental results were analysed concurrently.

Study on IoT and Cloud-based Smart Living Room Ventilation System with Real-Time Remote Control and Inspection

Currently, fire zone smoke control systems are installed with other systems, such as indoor air control, lighting, and communication, in large scale buildings, such as exhibition halls, marts, and multiplex malls, making it difficult to access and identify the required system. Additionally, most fire zone smoke control equipment are installed in a high position and most of the places are covered the ceiling with finishing material after installation, so inspection and maintenance are difficult and dangerous. By developing a smart fire zone smoke control system, an authorized person can remotely inspect and control it via the internet. Additionally, the real-time self-testing function enables constant inspection and confirmation. Furthermore, the smart living room ventilation system is installed in a duct dedicated to smoke control or combined with air conditioning and ventilation to ensure reliable smoke control performance. By remotely controlling the smart living room ventilation system according to the fire site, it is possible to delay the smoke descent time to the minimum and secure a safe evacuation route.

A package for piezoresistive pressure sensors with embedded built-in self-test function based on bimetallic actuator

Piezoresistive pressure sensors have been widely used in the industry and many other fields. However, conventional pressure sensor inspection is performed with the device off, which causes several inconveniences. In this article, an electrothermal actuator is designed and fabricated on the basis of bimetallic alloy material to realise the self-test of the piezoresistive silicon pressure sensor, and a kind of pressure sensor package structure with self-test capability is developed using the electrothermal actuator. Experimental results show that the structure can realise the dual excitation of the pressure and temperature of the diffused silicon pressure sensor core and enable it to return to the normal working state in less than 3.3 s. The self-test module can be driven at a low voltage of 0.8 V at less than 618 mW and can reflect the performance of the pressure sensor quickly and accurately. The structure is suitable for most differential pressure, absolute pressure sensor chips.

Intelligent Health Diagnosis of Lithium Battery Pole Double Rolling Equipment Driven by Hybrid BP Neural Network and Expert System

At present, the fault diagnosis methods of lithium battery pole rolling mill mostly rely on manual experience and the self-test function of mature control devices such as frequency converters and lack the ability of intelligent fault diagnosis for the whole equipment and the ability to evaluate the health state of the equipment during operation. To improve the intellectual health diagnosis ability of lithium battery pole double rolling mill equipment, starting from the structure and technology of lithium battery pole double rolling equipment, this paper analyzes its common fault types. It summarizes the shortcomings and common fault types of existing equipment. Then, we introduce fuzzy reasoning into the fault diagnosis method based on Expert Systems and establish the FEFDM of lithium battery pole double rolling equipment. Finally, we introduce the concept of health degree, effectively connect BP neural network and health degree through the fuzzy set, and establish an equipment operation health state evaluation method based on an improved BP Neural Network, which realizes the evaluation ability of the health state of double roller equipment. In addition, we use Extended Kalman Filtering (EKF) to clean the “dirty data” and filter out the Gaussian white noise from the signal. The health diagnosis method proposed in this paper can meet the ability to accurately locate and diagnose the fault of lithium battery pole double roller equipment and evaluate the health state of equipment operation and maintain the equipment in advance.

Implementation of a built-in self-test for nuclear power plant FPGA-based safety-critical control systems

Field-programmable gate arrays (FPGAs) are being widely used in the instrumentation and control (I&C) systems of nuclear power plants (NPPs). However, FPGAs have the possibility of failure, resulting in the reliability not being fully guaranteed; therefore, some methods are required to evaluate and verify their reliability. The built-in self-test (BIST) method is a technology that implants relevant functional circuits into another circuit during design to provide self-test functions. It has many advantages over external test devices. For this study, the FPGA-based reactor protection subsystem of the CPR1000 NPP was selected as the test object. This paper presents the principle of system partition, the main objective of which is to reduce the test time and provide convenience for subsequent modifications; then, we use the BIST method and build the BIST architecture to test each input signal channel as a black box. For several common failures, 100% diagnostic coverage can be obtained, which improves the reliability of a protection system. BIST can be used as a supplement to external tests; it can reduce the test time, reduce testing costs, and solve many problems that cannot be solved using external tests, such as the lack of interfaces. The research results provide theoretical and technical references for the application and review of FPGA-based applications in NPP safety–critical systems.

The Acceptance of Braille Self-Learning Device

The blind and visually impaired individuals are the citizens that exists in any society. Their blindness and visual impairment prevent them from using computers, operating digital devices, learning educational software, and restricting them from gaining certain knowledges. One of the most proven techniques for people with visual impairments to gain knowledge is to become proficient in Braille. Braille is represented by six dots arranged in a 3x2 matrix and can be read receptively only by the sense of touch. The common way of learning Braille is one-to-one technique between students and teachers. They use bulky devices which is inconvenient, not portable and costly. In fact, learning Braille always requires teachers to be present. People with visual impairments need special tools or tutorials to master the Braille language. This research introduces Braille Fingers Puller (BFP) self-learning device which is autonomous, low-cost, user-friendly, and portable with self-learn and self-test functions. Prior to the current device development, a Braille Finger Puller acceptance model is proposed based on seven factors that influence the BFP behavioral pattern which are perceived usefulness, perceived ease of use, performance, satisfaction, emotion, attitude, and comfort. The Braille Fingers Puller is tested with the blind association and finding shows that all factors except comfort factor have high score toward the intention to use BFP. Further improvement of the self-learning device is suggested in order to make it more comfortable for the visually impaired person to use.

An On-Line Testing Technique for the Scheduler Memory of a GPGPU

The highly parallel processing capabilities and reduced power performance of General Purpose Graphics Processing Units (GPGPUs) have been crucial factors for their massive use in multiple fields, such as multimedia and high-performance computing applications. Nowadays, more demanding areas, such as automotive, employ GPGPU devices where safety and reliability are mandatory design constraints. Nevertheless, the structural complexity, the transistor density, and the implementation in the latest silicon technologies introduce challenges to match safety and reliability requirements. In these technologies, wear-out and aging are factors that may significantly increase the occurrence of permanent faults during the lifetime operation. Moreover, these faults may generate unacceptable misbehaviors during the execution of an application. These constraints require devising new methods for in-field fault detection, thus verifying the integrity and correct behavior of the device during its whole operational life. This work proposes a technique to generate functional self-test programs targeting the detection of permanent static faults in the memory of the warp scheduler of a GPGPU. The proposed technique can translate fault primitives, which represent the effect of faults in a memory cell, into self-test functions and programs composed of a sequence of operations to excite the fault in the memory and to propagate its effects to a visible location, thus detecting its presence. We focused on the memory in the warp scheduler because it represents a crucial module for the device operation. Furthermore, this memory is present in each Streaming Multiprocessor (SM) of a GPGPU. Some experimental results to validate the method have been gathered, resorting to the NVIDIA Visual Profiler and the Nsight Debugger using the NVIDIA-GEFORCE GTX GPU platform and a structural fault simulator. The CUDA programming environment was used to implement the test procedures.

MEMS thermal gas flow sensor with self-test function

In this paper, the design, fabrication and characterization of a MEMS thermal gas flow sensor with self-test function are presented. The flow sensor is composed of a platinum heater and thermopiles, where the heater is served as a heat source and the thermopiles are used for voltage output. In order to improve the performance of the flow sensor, the heavily doped N/P-polysilicon is utilized to form the thermocouple and XeF2 front-side isotropic etching is adopted to realize thermal isolation of the device. At the same time, the effects of the chip position in the gas channel and heater voltage on device performance are also studied from both experiment and simulation. Moreover, a self-test method and corresponding test system based on the thermal flow sensor are proposed, which use an equivalent heater voltage to simulate the gas flow rate for monitoring the dynamic response of the flow sensor to the gas. This method is simple and effective compared with traditional methods for detecting the performance flow sensors. In addition, the basic output performance of the flow sensor using nitrogen as the test gas is characterized. The experimental results show that the flow sensor owns a relatively high sensitivity of 123.006 mV (m/s)−1 (no amplification), a low response time of about 250 ms and good accuracy of ±1.97%.

Design, fabrication, and characterization of a high-performance CMOS-compatible thermopile infrared detector with self-test function

This paper presents the design, fabrication and characterization of a CMOS-compatible thermopile infrared (IR) detector with self-test function based on XeF2 front-side dry etching. In order to achieve better performance, a heavily doped N/P-polysilicon is utilized to form thermocouples, and front-side isotropic etching is adopted to release and thermal isolation. At the same time, a platinum heater on the absorption layer is designed to serve as a heat source to realize the self-test function of the thermopile IR detector. IR radiation sensing shows that the detector achieves relatively high responsivity of 160.03 V W−1 and detectivity of and a extremely short response time of 2.5 ms in air at room temperature. In addition, a self-test measurement is conducted and validated by applying a voltage to the heater. Compared with traditional methods for detecting thermopile performance, this method has obvious convenience and simplicity, which provides an effective way for performance monitoring of thermal-based devices.

A ΣΔ Closed-Loop Interface for a MEMS Accelerometer with Digital Built-In Self-Test Function.

Sigma-delta (ΣΔ) closed-loop operation is the best candidate for realizing the interface circuit of MEMS accelerometers. However, stability and reliability problems are still the main obstacles hindering its further development for high-end applications. In situ self-testing and calibration is an alternative way to solve these problems in the current process condition, and thus, has received a lot of attention in recent years. However, circuit methods for self-testing of ΣΔ closed-loop accelerometers are rarely reported. In this paper, we propose a fifth-order ΣΔ closed-loop interface for a capacitive MEMS accelerometer. The nonlinearity problem of the system is detailed discussed, the source of it is analyzed, and the solutions are given. Furthermore, a built-in self-test (BIST) unit is integrated on-chip for in situ self-testing of the loop distortion. In BIST mode, a digital electrostatic excitation is generated by an on-chip digital resonator, which is also ΣΔ modulated. By single-bit ΣΔ-modulation, the noise and linearity of excitation is effectively improved, and a higher detection level for distortion is easily achieved, as opposed to the physical excitation generated by the motion of laboratory equipment.

Improved scheme for the determination of methanol using a two-dimensional photonic crystal

ABSTRACTThis paper reports a new method of detecting the concentration (mol L−1) of methanol by the use of a two-dimensional photonic crystal slab. Photonic band gap parameters are calculated using the plane wave expansion method. To find a model which has higher accuracy and practicality or applicability, fill factors used to analyze and compare the properties of the slab were computed. There is a linear proportional relationship between photonic band gap and dielectric constant of solution, which can be utilized to measure the concentration of methanol. The start frequency and the cutoff frequency also have a linear relationship with the dielectric constant of solution. The results show that a honeycomb lattice structure possesses better self-test functionality.

An Analog-Digital Mixed Measurement Method of Inductive Proximity Sensor.

Inductive proximity sensors (IPSs) are widely used in position detection given their unique advantages. To address the problem of temperature drift, this paper presents an analog-digital mixed measurement method based on the two-dimensional look-up table. The inductance and resistance components can be separated by processing the measurement data, thus reducing temperature drift and generating quantitative outputs. This study establishes and implements a two-dimensional look-up table that reduces the online computational complexity through structural modeling and by conducting an IPS operating principle analysis. This table is effectively compressed by considering the distribution characteristics of the sample data, thus simplifying the processing circuit. Moreover, power consumption is reduced. A real-time, built-in self-test (BIST) function is also designed and achieved by analyzing abnormal sample data. Experiment results show that the proposed method obtains the advantages of both analog and digital measurements, which are stable, reliable, and taken in real time, without the use of floating-point arithmetic and process-control-based components. The quantitative output of displacement measurement accelerates and stabilizes the system control and detection process. The method is particularly suitable for meeting the high-performance requirements of the aviation and aerospace fields.

In-Place Signal and Power Noise Waveform Capturing Within 3-D Chip Stacking

Three-dimensional chip stacking technologies have rapidly progressed in market deployments, calling the strong needs for design and validation techniques of 3-D integrated circuits (ICs). This paper proposes the hybrid of at-speed testing and waveform-based diagnosis for searching the optimum and stable operating conditions of 3-D ICs in an adaptive way to electric properties of a stacked chip structure. A functional silicon interposer features in-place waveform capturing and diagnosis for the quality of signaling and the integrity of power distribution networks (PDNs) deeply within a 3-D chip stack. In-place captured waveforms and eye diagrams are experimentally demonstrated and prove a solid data link operation through vertical TSV channels of 4096-b wide input/output (I/O) bus at the rate of 100 GB/s. While the built-in at-speed self-test functions confirm the bit error rates, the waveform-based diagnosis provides the optimum selection of driving strengths among mini I/O transceivers. The test and diagnosis features therefore play individual roles in validating 3-D IC operations, and exhibit strong correlations in their respective measurements.

3-D Hetero-Integration Technologies for Multifunctional Convergence Systems

Since CMOS device scaling has stalled, three-dimensional (3-D) integration allows extending Moore's law to ever high density, higher functionality, higher performance, and more diversed materials and devices to be integrated with lower cost. 3-D integration has many benefits such as increased multi-functionality, increased performance, increased data bandwidth, reduced power, small form factor, reduced packaging volume, because it vertically stacks multiple materials, technologies, and functional components such as processor, memory, sensors, logic, analog, and power ICs into one stacked chip. Anticipated applications start with memory, handheld devices, and high-performance computers and especially extend to multifunctional convengence systems such as cloud networking for internet of things, exascale computing for big data server, electrical vehicle system for future automotive, radioactivity safety system, energy harvesting system and, wireless implantable medical system by flexible heterogeneous integrations involving CMOS, MEMS, sensors and photonic circuits. However, heterogeneous integration of different functional devices has many technical challenges owing to various types of size, thickness, and substrate of different functional devices, because they were fabricated by different technologies. This paper describes new 3-D heterogeneous integration technologies of chip self-assembling stacking and 3-D heterogeneous opto-electronics integration, backside TSV fabrication developed by Tohoku University for multifunctional convergence systems. The paper introduce a high speed sensing, highly parallel processing image sensor system comprising a 3-D stacked image sensor with extremely fast signal sensing and processing speed and a 3-D stacked microprocessor with a self-test and self-repair function for autonomous driving assist fabricated by 3-D heterogeneous integration technologies.

Applications of three-dimensional LSI

Abstract

적외선영상 탐색기 표적 모의장치 개발

This paper describes the development of Target Simulator developed for performance test and failure detection of Imaging Infra-Red(IIR) seeker which is one of the most important equipments in specific cruise missile systems. The simulator makes it possible to test detecting and tracking performance for target, uniformity of IIR, FOV status and spatial resolving power. Besides, it includes several self-test functions and optic axis alignment methods to improve its own reliability.

Hardware Design of Test System for Missile Flight Control System

Before final assembly and while debugging a missile, in order to ensure the flight control system can work stably and reliably, it is necessary to develop an auto test system for a general performance test, including electrical performance, inertial measurement device and navigation accuracy. After describing the composition and working principle of the flight control system, summarizing the test requirements, this paper puts forward to a test plan based on a industrial computer, introduces the hardware design and hardware anti-jamming techniques in detail. The test system with self-test function has been applied in testing the flight control system generally and reliably.