Performance Test Methods Research Articles

An frequency domain analysis method of thermal parameters unsteady-state detection of building wall

ABSTRACT The in-situ inspection technology of thermal properties of building wall is an important technical guarantee to achieve the goal of building energy conservation. However, there is still a lack of fast, simple, and accurate unsteady-state detection method under natural conditions. This paper focuses on the thermal performance test and analysis method of building wall under natural condition. Two frequency domain analysis methods were developed for the thermal conductivity, as well as volume specific heat and thermal inertia of homogeneous wall along with the harmonic reaction method and the frequency domain analysis theory. The frequency response relationship between the internal and external surface temperature waves and indoor air temperature waves was established, and the relationship contains thermal performance parameters of wall. The thermal conductivity and specific volume heat of wall can be solved by using the response relation. Numerical simulation verification of the method was completed by using ANSYS software and the experimental verification by using wall insulation materials were accomplished in the laboratory. The maximum relative error of numerical simulation results is 1.48%, and that of laboratory experiment results is 8.75%. The implications of these results with respect to the influence on the in-situ inspection technology of building wall are discuss.

Electrochemical Capacitors: Performance Metrics and Evaluation by Testing and Analysis

AbstractElectrochemical capacitors (i.e., supercapacitors) as energy storage technologies have attracted a lot of attention because of the increasing demand for efficient high‐power delivery. Over the past decades, various advanced electrode materials and cell design have been developed to improve the performance of electrochemical capacitors. Hybrid capacitors and pseudocapacitors achieve much higher energy density due to their fast surface redox reactions. However, although all of them can be classified as electrochemical capacitors, different charge storage mechanisms alter their electrochemical characteristics. All the speculation and potential uncertainties, in the absence of standard performance metrics and test method, make it rather challenging to reliably evaluate the performance of various electrochemical systems, which hinder the development of advanced energy storage technologies and make the comparison between different energy storage systems (batteries, electrochemical capacitors, and hybrid devices) not so meaningful. In this regard, the uncertainties related to the performance metrics and evaluation of electrochemical capacitors are summarized and the ways in which the uncertainties can be minimized for both electric double layer capacitors (EDLCs) and hybrid supercapacitors is analyzed. It is hoped this effort will provide an accurate assessment method for determining the device properties to a high level of confidence and promote the standardization process of performance evaluation for the electrochemical energy storage systems.

Durability assessment of structural sealant glazing systems applying a performance test method

ABSTRACT During the service life of a Structural Sealant Glazing (SSG) facade, its silicone bond is simultaneously exposed to climatic and mechanical loads. Current durability assessment methods yet schedule separate test programmes for accelerated weathering and mechanical loading. This study presents a durability test that applies mechanical loading and weather cycling simultaneously simulating 50 years of use. Two common structural sealants are tested. The mechanical behaviour of medium-scale system specimens in tension, compression and shear is recorded for performance assessment during exposure. Moduli and dissipated energies show a characteristic decrease, indicating stress relaxation and degradation. Tensile and shear moduli and strengths of sections cut out from the system specimens after exposure are notably reduced by combined loading compared to those of reference and weathered specimens. Differences between performance and durability characteristics of the two sealants are consistent, also regarding supplementary visual inspection and hardness measurements. The approach introduced in this article provides a basis for more comprehensive performance-related durability testing of SSG-systems.

Critical Insight Into Performance Requirements and Test Methods for Surge Protective Devices Connected to Low-Voltage Power Systems

Surge protective devices, SPDs, improve the reliability of power systems by mitigating the risk of equipment failure due to impinging overvoltages. The role of SPDs is more challenging today when considering the advent of smart grids and the associated integration of sensitive electronic equipment into modern low-voltage power systems. This work provides critical insight into performance requirements and test methods for surge protective devices according to IEC 61643 and UL 1449 standards; SPD ratings and fail-safe behavior are on focus. Experimental arrangements are proposed to represent in a laboratory environment the surge current and/or temporary overvoltage events that SPDs may be exposed to in the field; experimental evidence, ATP-EMTP simulation results and field experience are used to support these proposals. Grey zones of SPDs performance and failure mode are discussed in the context of the integrated components technology.

Performance Parameter Analysis of Power Cable Modified Polypropylene (MPP) Conduit

Modified polypropylene (MPP) conduits are increasingly used as protection conduits for trenchless power cables. In order to ensure the performance and quality of MPP conduits used in the field of power cables, this article has carried out research on its performance parameters and test methods. First of all, in view of the problem of excessive deviation of the MPP conduits appearance and size inspection, the relationship between the conduits wall thickness and the mechanical performance ring stiffness parameter was studied. Then, through the MPP conduits density, ring stiffness, Vicat softening temperature, and flattening test results, the correlation between the three parameters of density, ring stiffness, and Vicat softening temperature is analyzed. It also concluded that the ring stiffness and Vicat softening temperature have a moderate positive correlation. Finally, the article compares some similarities and differences between the MPP conduit and the CPVC conduit for two power cable protection conduits in terms of performance parameter test items.

Fitness Testing Parameters for Alpine Ski Racing

ABSTRACT Alpine ski racing requires high levels of isometric, eccentric, and concentric muscle actions through wide ranges of hip, knee, and ankle mobility. The course duration of ∼40 seconds for slalom racing to upward of 2.5 minutes for downhill racing necessitates high levels of anaerobic endurance, aerobic power, and force production to be successful. In addition, due to the highly technical skill aspect of ski racing, neuromuscular coordination is of utmost importance. This review identifies the most effective performance testing methods for alpine ski racing, as well as highlighting their relevance to the physiological parameters of the sport.

함정탑재장비용 대용량 마운트의 성능검증시험방안

The mounts installed in the main engines and generators among the naval shipboard equipment require a relatively large capacity and are one of the parts that localization development is proceeding. In order to develop these parts, an effective evaluation method must be established so that it can be applied from the design stage. In this paper, two general performance testing methods applicable to large capacity mounts are proposed. We review some US military specifications, determine necessary test items, and propose supplemental measures by considering the domestic test evaluation environment. However, the proposed method can be applied only to resilient rubber mounts.

Simplified Calculation of Energy Efficiency Index for Plate Heat Exchanger

Based on GB/T 27698.3-2011 heat exchanger and heat transfer element performance test method Part 3: Plate heat exchanger, a simplified method for the calculation of energy efficiency index is proposed other than just experimental data required by NB/T 47004.1-2017 plate heat exchangers-part 1: plate-and-frame heat exchangers. The new equation of EEI in term of 12 parameters δρ , λρ , lh,l c, dh,d c, Ch,Cc,ah, bh,ac,bc incorporates both fitted correlations of experimental result and parameters for fluid physical properties and working conditions. Therefore, the method omits the intermediate processes such as total heat transfer coefficient k and pressure drops for both sides. It also solves the accuracy problem that deviates from the standard working conditions and is difficult to realize practically. The new test of high cost is unnecessary to obtain the energy efficiency index for old plate heat exchangers with part experimental data or correlations.

Antenna Performance Test Method and Result Analysis for V2X Communication of Connected Vehicle

This paper proposes an antenna performance test method for vehicle-level to ensure the stable communication capability for vehicular networking technology and application. Firstly, considering the large size and heavy weight of characteristic for the vehicle, a spherical near-field test for the vehicle antenna test is then proposed in the paper. Secondly, the impact of the vehicle body on the antenna performance is analysed by comparing the different performance between different vertical angles and antennas. Finally, the experimental results verify the validity and correctness of this method.

Server and Storage Performance Testing for Data Center Construction

The increase in data triggered by the smartphone revolution has led to a growing interest in cloud-based data centers. However, while much research has been conducted on virtualization technologies for cloud data centers, there has not been enough research on the performance of physical systems. As manufacturers only provide performance figures measured in their own system’s favor, objective and consistent performance testing metrics and methods are needed for performance measurement. This paper suggests some performance testing metrics and methods for cloud-based physical systems using TPC, SPECjbb and SPC.

Comparison of The Use of Number and Type of Spark Plugs on One Cylinder Gasoline Machine Performance

<p class="Judul">The basic concept of a combustion motor is to convert chemical energy into heat energy and then convert it to mechanical energy. Heat energy is produced from the combustion process between a mixture of fuel and air with a pressure difference triggered by spark (flame). The objective is to determine the difference in power, torque, and average effective pressure by adding the number of spark plugs and using the standard type of spark plug and iridium on a single-cylinder engine. The engine performance testing method uses P-max to get power, while the analysis uses experimental design, the data processing method uses DOE-factorial and the Minitab application 18. Power test for a standard spark plug resulted in 7.93 HP, 0.89 kgm torque and 1207.66 kPa average effective pressure. For iridium spark plug the test produced 9.02 HP, it is 0.91 kg.m for torque and average effective pressure is 1226.32 Kpa. For two standard spark plugs, the power was 9.38 HP, torque was 0.93 kg.m, and the average effective pressure was 1269.96 kPa. Whereas the two iridium spark plugs produced 9.59 HP, 0.91 kg.m torque, and 1277.78 kPa average effective pressure.</p>

Performance test methods for near‐infrared fluorescence imaging

PurposeNear‐infrared fluorescence (NIRF) imaging using exogenous contrast has gained much attention as a technique for enhancing visualization of vasculature using untargeted agents, as well as for the detection and localization of cancer with targeted agents. In order to address the emerging need for standardization of NIRF imaging technologies, it is necessary to identify the best practices suitable for objective, quantitative testing of key image quality characteristics. Toward the development of a battery of test methods that are rigorous yet applicable to a wide variety of devices, we have evaluated techniques for phantom design, measurement, and calculation of specific performance metrics.MethodsUsing a NIRF imaging system for indocyanine green imaging, providing excitation at 780 nm and detection above 830 nm, we explored methods to evaluate uniformity, field of view, spectral crosstalk, spatial resolution, depth of field, sensitivity, linearity, and penetration depth. These measurements were performed using fluorophore‐doped multiwell plate and high turbidity planar phantoms, as well as a 3D‐printed multichannel phantom and a USAF 1951 resolution target.Results and ConclusionsBased on a wide range of approaches described in medical and fluorescence imaging literature, we have developed and demonstrated a cohesive battery of test methods for evaluation of fluorescence image quality in wide‐field imagers. We also propose a number of key metrics that can facilitate direct, quantitative comparison of device performance. These methods have the potential to facilitate more uniform evaluation and inter‐comparison of clinical and preclinical imaging systems than is typically achieved, with the long‐term goal of establishing international standards for fluorescence image quality assessment.

Design of Lane Departure Warning System Based on Fuzzy Control Mode of Android System

Aiming at the unconscious lane departure behavior in the process of driving, a design scheme of lane departure warning system based on Android is proposed. STM32F103C8T6 is selected as the main control chip and CAN bus communication technology is used to collect vehicle information such as vehicle speed, steering angle and steering signal. Then Bluetooth module is used to transmit the data to the mobile phone for real-time processing. Taking GB/T 26773-2011 (Performance Requirements and Test Methods for Lane Departure Alarm System) as the design standard, the lane departure rate ε and the time T when the right front wheel crosses the lane line are considered as the input of the two-dimensional fuzzy controller, and the early warning level W is considered as the output. When the driving deviation angle is 5°, the interval of the lane departure rate ε is [0.75,1.35], and the interval of T is [0,1.5]. After normalized parameter processing, a certain fuzzy interval is set according to the driving habits of different vehicle drivers, and the fuzzy control algorithm with improved membership function is adopted for control, so as to improve the recognition rate of lane lines, reduce the early warning misjudgement rate and reduce the incidence of traffic accidents.

Performance Simulation for the Supporting Structure of Aero-Engine Rotor in Wide Frequency Domain

The inertia load of aero-engine indeterminate rotor support is calculated by the finite element method coupled with plane stress element and Fourier ring element. Without considering the dynamic characteristics of rotor’s supporting structure, the test results are error-prone and inefficient. A new method for testing the supporting structure performance of aero-engine rotor in wide frequency domain is proposed. On this basis, the structural model of the casing-support and the structural model of aero-engine rotor are constructed by substructure modelling method. Combining the two sub-models, the semi-physical simulation model of the vibration of the engine rotor’s supporting structure is obtained. By superimposing the additional dynamic stiffness matrix of the casing-supporting structure at the designated DOF position in the overall stiffness matrix of the finite element model of the rotor structure, the overall stiffness matrix of the aero-engine rotor supporting structure is obtained. The effective stiffness matrix can be used to calculate the structural dynamic characteristics of aero-engine rotor supporting structure. Experiments show that the average error of the proposed method is 0.0023 and the number of units is 7.98 e4. The calculation time and storage space are reduced by 310 minutes and 166 GB respectively compared with the performance test method of rotor support based on finite element analysis, which shows that the proposed method is more efficient and accurate.

The Investigative Study on the Small-sized Isolation Device: regarding of the isolation performance and function test In Emergency Disaster Circumstances

The first case of Middle East Respiratory Syndrome (MERS) was reported in Korea in 2015, after a Korean man from Bahrain tested positive for the infection. After first eruption, there were numbers of secondary infectees and whole country were frightened. At the time, isolated ambulances were available but few, and there was no specific way to prevent contamination during transfer. Therefore, Seoul National University Hospital and the University of Seoul developed isolation units and air filters. Four years after the MERS outbreak, this study measured the differential pressure inside and outside the small isolation units based on the differential pressure and air flow derived from simulation and testing, and proposed minimum values for virus leakage and internal sealing. A performance evaluation and testing method for the transfer equipment is proposed. The critical function of the small isolated transport equipment was defined and selected as an evaluation item; performance evaluation was carried out by simulating a real-world case. The results provide the proper pressure configuration of positive and negative pressure inside the segregation feeder; the clear criteria for the HEPA filter; and the performance criteria for the segregation feeder and air purifier.

A Standard Method for Performance Detection of Fluorescence Imaging System

Fluorescence imaging now becomes an intraoperative navigation technique that gaining popularity in surgery and clinical research. However, at present, there is no mature and reliable method or other related guidance documents for the detection of fluorescence imaging performance. The performance analysis and quality supervision of products on the market could not be performed, which affects their clinical use and image quality. In this paper, a standard method of fluorescence imaging performance testing for fluorescence imaging system is proposed. Several kinds of fluorescence imaging performance parameters affecting fluorescence images are defined strictly. We also recommend scientific and feasible methods for their detections and analyses, which are verified by practical examples. This paper aims to provide a feasible reference standard for fluorescence performance evaluation.

Process operation optimization using system identification

Process optimization is an important topic in process industry, most process industry optimization works are based on mechanism models or performance test methods. However, it is very difficult to carry out optimization in actual operation because of the difficulty in obtaining the mechanism model, the difficulty in on-line measurement of objective function and the high test cost. In order to solve the problem, an online optimization method based on system identification is proposed. By replacing the unmeasurable variable with the measurable variable, the process model is identified on-line, and the gain of identified model is used as the optimization gradient to find the optimal variable value on-line. The method is verified using both simulation and real plant data.

Method for Prototyping and Testing the Information Minimalism Concept of Nuclear Power Plants

he information structure and visualization design in nuclear power plant is based on careful analysis and understanding of the work domain of the operator. Piping and instrumentation diagram (P&ID) based layouts tend to require more display space. Overuse of mimic layouts can result in visual clutter. P&ID based layouts of controls are usually less easily operated configurations than those provided by other array conventions. Thus, a display method is emerging to minimize P&ID based display. The information minimalism concept is a monitoring and controller display method for each operation mode based on log analyses of operator actions. This method provides the monitoring information and control means necessary for the operator, according to operation mode, to perform a specific operation. This method can reduce the time spent searching for information and the transition between display pages. The aim of this paper was to verify the feasibility of implementing new concepts by establishing an information minimalism prototype. The validity of the function, performance, and operational test methods were verified by testing one such information minimalism prototype. In this paper, we describe prototyping and testing methods for the information minimalism concept for NPPs. In the future, this concept is to be added to the concept of operator support with the existing display configuration and navigation, and thereby extend its application range while actually utilizing it.

Study on influence factors of Intelligent Connected Vehicle (ICV) performanc under Complex Weather Conditions

At the moment, ICV performance test method doesn’t exist yet under the complex weather conditions, the revolution of ICV is greatly limited. By studying the weather environment that influence ICV, the meteorological indicators which influence ICV performance will be acquired. Then by analyzing the main complex meteorological factors, their scene characteristics and main control indexes are given. It provides a basis for the construction of the complex weather scene and the research of the test method of ICV under the complex weather condition.

Analysis of Energy Saving and Consumption Reduction Effect of Ejector confluence on Heating Unit

Achieving the utilization of thermal energy according to its quality is the main means for power generation enterprises to improve the efficiency of primary energy utilization. This paper introduces the application of ejection confluence technology in 330 MW unit of a factory, and calculates and analyses the energy saving effect under the ejection confluence mode based on the method of thermal performance test. The results show that when the unit load is above 210 MW, the average energy saving of ejector-confluence heating mode is 2.18 g/(kW·h) relative to reheat heating mode.