游戏软件测试模式选择与测试估计研究

通过对游戏软件特有的测试模式分析,进行游戏软件测试工作量估计.以美国软件生产力研究所(Software Productivity Research)的一般软件测试估计的数据为基础,以网络游戏为例,选择了12个测试阶段为游戏软件测试模式,对游戏软件测试工作量进行估计.通过3个游戏项目的实验对比,测试估计的误差在15%～20%之间.指出进一步收集并构建游戏软件测试数据,确定数据调整因子的研究方向.

大跨度房屋建筑工程中预应力的估计与测试

当前房屋建筑工程中预应力评估与测试方法的用户满意度和评估结果均与实际值拟合度较低、能耗高,提出新的大跨度房屋建筑工程中预应力的估计与测试方法。将建筑截面预应力的储备度、预应力储备度的衰减率和名义裂缝宽度作为大跨度房屋建筑工程中预应力衰减程度评估指标,完成房屋建筑工程预应力程度的分级。利用Ansys模拟软件对房屋建筑预应力进行模拟测试,通过选择单元类型、模拟预应力值、网格划分和设置边界条件,得到房屋建筑预应力模拟测试前两阶振型,结合房屋建筑工程中预应力衰减程度评估结果,得到房屋建筑工程中预应力值,实现大跨度房屋建筑工程中预应力的估计与测试。实验结果表明,所提方法用户满意度和评估结果与实际值拟合度高、方法运行能耗平均为60.7 J。该方法整体性能优于当前相关方法,可为建筑行业发展提供一定的理论支撑。

顺序故障诊断策略的测试费用期望值估计

文章研究顺序故障诊断策略,试图最小化测试费用的期望值;阐述了3种经典算法及其思想,对信息熵和贪婪算法进行了深入讨论;基于信息熵的贪婪算法,给出其测试费用期望值的一个上下界;当测试集满足一定特征且测试费用相等时,给出了基于Huffman算法的一个估计。

测试工时受限的测试策略研究

为在有限工时内对软件进行尽可能充分的测试,提出了测试工时受限的测试策略。提出了一种在测试用例设计前预估其优先级的方法;依据测试需求、计划采用的测试类型及测试设计方法,估算出预计产生的各类测试用例的优先级、数量、单位用例所需的测试工时;采用提出的测试用例选择方法,选择出尽可能多的优先级高的测试用例,力保每个功能至少被一个合法测试用例所覆盖,确保在有限的测试工时内,能够完成这些测试用例的设计和执行。通过实验验证了该测试策略的有效性。

New method of online testing and data processing for LED lamps

In order to achieve quick and accurate lifetime prediction of LED lighting products under the testing time of 2 000 h, a method of online testing of luminous flux is proposed under the condition of temperature stress.Exponential fitting of lumen maintenance, the Bayesian estimation of failure probability, the Weibull distribution of lifetime and the Arrhenius model of the decay rate are used in combination to acquire the distribution of failure probability over time at the ambient temperatures of 25 ℃. The lifetime test of the same lamps based on the Energy Star standard under the testing time of 6 000 h is also implemented to verify the effectiveness of the method. The errors of lifetimes acquired with the proposed method are 7%, 4%, 3% and 1% at the failure probabilities of 62. 3%, 10%, 5% and 1%,respectively.

Structural damage identification using test static data based on grey system theory

A new structural damage identification method using limited test static displacement based on grey system theory is proposed in this paper. The grey relation coefficient of displacement curvature is defined and used to locate damage in the structure, and an iterative estimation scheme for solving nonlinear optimization programming problems based on the quadratic programming technique is used to identify the damage magnitude. A numerical example of a cantilever beam with single or multiple damages is used to examine the capability of the proposed grey-theory-based method to localize and identify damages. The factors of meas-urement noise and incomplete test data are also discussed. The numerical results showed that the damage in the structure can be localized correctly through using the grey-related coefficient of displacement curvature, and the damage magnitude can be iden-tified with a high degree of accuracy, regardless of the number of measured displacement nodes. This proposed method only requires limited static test data, which is easily available in practice, and has wide applications in structural damage detection.

Study and Application of Objective Evaluation Model on Fabric Style

Based on 31 fabric property parameters tested by FAST test system and other test instruments, the principal factors of fabric style are obtained through the principal factor analysis method and computer program. According to the correlation between each parameter and principal factor, the selected positive or negative coefficient, the objective evaluation model of fabric style has been established based on the percentage of variance. And wool fabrics have been taken for example to show how to use the objective evaluation model for fabric design.

Which Endpoints Can Be Reliably Assessed in Semi-field Pollinator Species Testing without Estimating False Positive or False Negative？ MDD’s and Replicates Issue

Statistical power, number of replicates and experiment complexity of semi-field and field studies on Apis and non-Apis bee species has become a major issue after publication of the draft European Food Safety Authority （EFSA） Guidance on risk assessment of plant protection products （PPP） on bees （Apis mellifera, Bombus spp. and solitary bees）. According to this guidance document, field studies have to be designed to be able to detect significance differences as low as 7% for certain endpoints such as reduction in colony size. This will require an immense number of replicates which is obviously not feasible. In the present study, key endpoints such as mortality, termination rate and number of brood cells in honeybee studies, cocoon production and flight activity in solitary bee studies and number of gynes in bumble bee studies （just to mention some of the endpoints considered） in semi-field studies were analyzed, with Apis mellifera, Bombus terrestris and Osmia bicornis during the past five years （2013-2017）. The results indicate huge differences in the percentage minimal detectable differences （%MDDs） （MDD expressed as median of control value of the endpoint in percent） depending on endpoint and species tested. For honeybee semi-field studies, the lowest %MDDs recorded were between 10% and 15% for the endpoints foraging, number of brood cells and colony strength. The highest %MDDs were observed for the endpoint termination rate, with a %MDD of almost 50%. For the endpoints in bumble bee semi-field studies the %MDDs varied between 17% for bumble bee colony weight and 53% for average mortality during the exposure period in the tunnel. The %MDD for the number of gynes （young queens） was slightly below 25%. For the semi-field solitary bee test system, the %MDDs for the measured endpoints seem to be lower than those for the other two species tested. The %MDDs for the endpoints hatching of offspring, nest occupation and number of cocoons were 8%, 13% and 14%, respectively. Most of the %MDDs were between 10% and 30% indicating clearly that the currently performed experimental design for the semi-field pollinator studies allowed to determine relatively small effects on key study endpoints. The analysis indicated that for all the three bee species tested, the semi-field test design detected low %MDDs for most of the endpoints. It was also observed that detectable differences between the control and PPP treatments were much lower in semi-field test designs than in field studies with these bee species. The “perfect sample size” really does not exist but test design and statistical analysis can be adapted to lower the %MDDs. Measured and simulated （according to Student’s t-test-distribution） data and results showed that statistical evaluations parameter selection （e.g., alpha value）, data transformation （log10） and the number of replicates had a direct effect on the ability of the test design to detect lower or higher %MDD values. It could show that a change of alpha value from 0.05 to 0.1, increases the ability of the studies to detect lower %MDDs. For most of the measured endpoints, increasing the number of replicates e.g., from four to eight, improved the power of the test design by decreasing the %MDD. The reduction magnitude of the %MDD is dependent on the endpoint and selection of statistical parameters such as the alpha value. Parameters that display effects at a biologically relevant scale will be a better indicator for effects than parameters that are able to detect minor differences that are not biologically relevant.

Tests of new in-situ seabed acoustic measurement system in Qingdao

A new in-situ seabed acoustic measurement system is developed for direct in-situ measurement of sediment geoacoustic properties （compressional wave velocity and attenuation）. The new in-situ system consists of two parts： the deck control unit and the underwater measurement unit. The underwater measurement unit emits sonic waves that propagate through the seafloor sediment, receives the returning signals, and transmits them to the deck control unit for waveform display and analysis. The entire operation is controlled and monitored in real time by the deck control unit on the research vessel and can provide recording of full waveforms to determine the sound velocity and attenuation. This paper outlines the design of the system, the measurement process, and demonstrates its application in tests carded out on seabed sediment off the Qingdao coast, China. The test results show that the system performed well and rapidly provided accurate in-situ acoustic velocity and attenuation estimates of the seafloor sediment.

Main Gas Pipelines： Fracture Resistance Assessment of Pipes

This paper proposes an estimation method of fracture resistance of oil ＆ gas pipes, based on the results of full scale hydraulic pressure pipe testing with the artificial notch, made by the authors at 2002-2006. It shows that the fracture process at the stage of stripping （initialization） of crack can be characterized by Critical Fracture Diagram （CFD）. Calculating and experimental way to construct CFD is suggested and discussed. The fracture resistance requirements for oil ＆ gas pipes in terms of fracture mechanics （Kc, Lc） are formulated and proved. The results of full scale hydraulic pressure pipe testing, based on metal testing data of the standard Charpy specimens （KCV） and pipe＇s specification requirements are interrelated. The way to estimate the admissible temperature operation conditions of oil ＆ gas pipes by means of based metal ＂KCV-temperature＂ dependence is proposed.

Fatigue Crack Initiation Sizing Using Acoustic Emission

One of the major concerns in structures is early detection of a growing crack to prevent fracture, predict remaining useful life, schedule maintenance and reduce costly downtimes. AE （acoustic emission） is a non-destructive testing method with potential applications for locating and monitoring fatigue cracks. This paper focuses on in-situ monitoring of structural health, specifically detection of small crack growth and crack initiation in structures using AE technology. A probabilistic AE-based model for small fatigue cracks was developed and the uncertainties of the model were estimated. The paper discusses the methodology used, experimental approach, results obtained and predictive models developed.The developed model can be used to evaluate the integrity of structures and assess structural health by estimating the probability density function of the length of detected cracks. The outcome of this research has significant potential to be used for in-situ monitoring and evaluation of structural integrity.

Research on Remote Aerobics Network Learning System based on B/S

through the design of teaching aerobics web-based course and application practice, the instructional design process based on B/ S learning are analyzed, and discusses several key problems in the design and teaching. This paper presents the resource based learning aerobics teaching design network course should adapt to the application mode of network teaching and traditional classroom combination; that will provide teaching demonstration, teaching contents for students as well as the function of self testing evaluation and provide the job management, teacher online Q ＆ A, database and knowledge base construction, greatly improving the ＂aerobics＂ teaching efficiency.

A study of laboratory testing and calculation methods for coal sorption isotherms

Measurement of the volume of gas adsorbed per unit mass of coal with increasing pressure at a constant temperature produces an isotherm that describes the gas storage capacity of this type of coal. The accurate testing and interpretation of coal sorption isotherm plays an important role in the areas of coal mine methane drainage, coalbed methane （CBM） reservoir resource assessment, enhanced coalbed methane （ECBM） recovery, as well as the carbon dioxide （CO2） sequestration in deep coal seams or similar geological formations. Different coal sorption isotherm testing apparatus and associated calculation methods are critically reviewed and presented in this paper. These include both volumetric and gravimetric based methods, as well as experimental sorption tests with confining stress and direction sorption methods. The volumetric techniques utilise experimental apparatus with sample cell and injection pump and that with both sample cell and reference cell. Whilst the gravimetric approachesinclude methods with sample cell and suspension magnetic balance and that with both sample cell and reference cell. Different testing methods are compared and discussed in this study. A unique in-house-built coal sorption isotherm testing apparatus at the University of Wollongong was presented together with the calculation method, procedures and experimental results. The isotherm results can be calculated by both Soave-Redlich-Kwong （SRK） equation and calibration cure methods which can be used directly to convert the volume of adsorbed gas in different test conditions to standard condition （NTP）.

Estimating Average Reservoir Pressure： A Neural Network Approach with Limited Data

Insight into average oil pressure in gas reservoirs and changes in production （time）, play a critical role in reservoir and production performance, economic evaluation and reservoir management. In all practicality, average reservoir pressure can be conducted only when producing wells are shut in. This is regarded as a pressure build-up test. During the test, the wellbore pressure is recorded as a function of time. Currently, the only available method with which to obtain average reservoir pressure is to conduct an extended build-up test. It must then be evaluated using Homer or MDH （Miller, Dyes and Huchinson） valuation procedures. During production, average reservoir pressure declines due to fluid withdrawal from the wells and therefore, the average reservoirpressure is updated, periodically. A significant economic loss occurs during the entire pressure build-up test when producing wells are shut in. In this study, a neural network model has been established to map a nonlinear time-varying relationship which controls reservoir production history in order to predict and interpolate average reservoir pressure without closing the producing wells. This technique is suitable for constant and variable flow rates.

小子样复杂装备系统测试性评估中的验前参数值确定方法

针对当前小子样测试性评估中对验前信息处理不规范、结果可信度差的问题,研究了由专家经验信息、子系统试验信息和虚拟仿真信息确定系统测试性验前参数值的方法.根据不同来源的测试性验前信息,分别提出了模糊不确定性加权、分系统数据折合和基于相似度量的Dempster-Shafer(D-S)证据融合方法估计系统测试性验前参数值.实例分析表明:该方法计算测试性评估中的验前参数值比其他文献方法的计算结果低约0.8%.

A linear varying coefficient ARCH-M model with a latent variable

Motivated by the psychological factor of time-varying risk-return relationship, this paper studies a linear varying coefficient ARCH-M model with a latent variable. Due to the unobservable property of the latent variable, a corrected likelihood method is employed for parametric estimation. Estimators are proved to be consistent and asymptotically normal under certain regularity conditions. A simple test statistic is also proposed for testing latent variable effect. Simulation results confirm that the proposed estimators and test perform well.The model is further applied to examine whether the risk-return relationship depends on investor's sentiment in American Market and some explainable results are obtained.

A classification-based method to estimate event-related potentials from single trial EEG

A novel method based on machine learning is developed to estimate event-related potentials from single trial electroencephalography. This paper builds a basic framework using classification and an optimization model based on this framework for estimating event-related potentials. Then the SingleTrialEM algorithm is derived by introducing a logistic regression model, which could be obtained by training before SingleTrialEM is used, to instantiate the optimization model. The simulation tests demonstrate that the proposed method is correct and solid. The advantage of this method is verified by the comparison between this method and the Woody filter in simulation tests. Also, the cognitive test results are consistent with the conclusions of cognitive science.