On-Line Testing of Lab-on-Chip Using Reconfigurable Digital-Microfluidic Compactors

Dependability is an important system attribute for microfluidic lab-on-chip devices. On-line testing offers a promising method for detecting defects, fluidic abnormalities, and bioassay malfunctions during chip operation. However, previous techniques for reading test outcomes and analyzing pulse sequences are cumbersome, sensitive to the calibration of capacitive sensors, and error-prone. We present a built-in self-test (BIST) method for on-line testing of digital microfluidic lab-on-chip. This method utilizes microfluidic compactors based on droplet-based AND gates, which are implemented using digital microfluidics. An optimization method is proposed to schedule logic AND operations in the compactor to minimize the end time for the compaction procedure. Dynamic reconfiguration of these compactors ensures low area overhead and it allows BIST to be interleaved with bioassays in functional mode. We evaluate the on-line testing method using a multiplexed in vitro diagnostics bioassay.     

An exact permutation method for testing any effect in balanced and unbalanced fixed effect ANOVA

The ANOVA method and permutation tests, two heritages of Fisher, have been extensively studied. Several permutation strategies have been proposed by others to obtain a distribution-free test for factors in a fixed effect ANOVA (i.e., single error term ANOVA). The resulting tests are either approximate or exact. However, there exists no universal exact permutation test which can be applied to an arbitrary design to test a desired factor. An exact permutation strategy applicable to fixed effect analysis of variance is presented. The proposed method can be used to test any factor, even in the presence of higher-order interactions. In addition, the method has the advantage of being applicable in unbalanced designs (all-cell-filled), which is a very common situation in practice, and it is the first method with this capability. Simulation studies show that the proposed method has an actual level which stays remarkably close to the nominal level, and its power is always competitive. This is the case even with very small datasets, strongly unbalanced designs and non-Gaussian errors. No other competitor show such an enviable behavior.     

The effect of testing location on usability testing performance, participant stress levels, and subjective testing experience

The effect of testing location on usability test elements such as stress levels and user experience is not clear. A comparison between traditional lab testing and synchronous remote testing was conducted. The present study investigated two groups of users in remote and traditional settings. Within each group participants completed two tasks, a simple task and a complex task. The dependent measures were task time taken, number of critical incidents reported, and user-reported anxiety score. Task times differed significantly between the physical location condition; this difference was not meaningful for real world application, and likely introduced by overhead regarding synchronous remote testing methods. Critical incident reporting counts did not differ in any condition. No significant differences were found in user reported stress levels. Subjective assessments of the study and interface also did not differ significantly. Study findings suggest a similar user testing experience exists for remote and traditional laboratory usability testing.     

The effect of fault size on testing

Software fault size (meaning the frequency of activation) is important when determining the merits of different testing methods. One of the purposes of testing is argued to be the identification of faults which, when removed, will contribute increases in reliability. The concept of size-effectiveness is defined here to distinguish those testing methods which are better at finding large faults. Methods of different size-effectiveness can be compared by measuring the distribution of sizes through a measure called the ‘operational testing efficiency ratio’ (OTER). This has significant implications for the way that one should view testing in particular and the software development process in general. © 1997 John Wiley & Sons, Ltd.     

Calcium dynamics in cardiac myocytes: a model for drugs effect description

Ca²⁺ dynamics and handling in cardiomyocytes are critical for both metabolism and contraction of the heart. Action potentials involve membrane and subcellular components. In response to membrane depolarization during an action potential, L-type Ca²⁺ channels open, allowing the influx of Ca²⁺ into a restricted subspace where it triggers Ca²⁺ release from the sarcoplasmic reticulum (SR) via ryanodine-sensitive Ca²⁺ channels (RyRs). This results in a global increase in the cytosolic Ca²⁺ concentration which triggers contraction through the contractile proteins. Relaxation follows the reuptake of Ca²⁺ into the SR by the Ca²⁺ pump in the SR (SERCA) or its extrusion from the cell essentially ensured by the Na–Ca exchanger. A model of Ca²⁺ handling model developed in a precedent work give us quite good results but its not sufficient to explain the cell behaviour in presence of some specific substance like arachidonic acid. In order to explain this difference the authors have developed a new model taking into account a modification of some specific components of the SR.     

Classic group testing with cost for grouping and testing

We generalize the classical group testing problem to incorporate costs associated with pooling and inspection, both of which are significant factors in actual applications. We formulate the expected cost model as a nonlinear integer programming problem, prove several propositions and a theorem concerning when pooling is more efficient than individual testing, and determine the optimal group size such that the expected cost is minimized.     

基于激光多普勒效应的MEMS的运动检测

提出了一种可以测量微机电系统（MEMS）面内瞬时速度和位移的测量系统。该系统利用差动激光多普勒效应,采用了频移技术和接收端的滤波技术将带有MEMS运动信息的光信号接收并解调,然后,利用LabVIEW和MaSab软件对采集的信号进行数字滤波和时频分析,从而得到被测器件的运动参量,为研究MEMS的动态特性提供了准确可靠的方法。     

面向化学品运输的车辆定位监控系统

介绍了一种基于GPS和GSM的短消息的危险化学品运输车辆定位监控系统,由车载终端、通信子系统、监控中心组成,并给出了系统方案和软、硬件实现方法。     

The OECD software tool for screening chemicals for persistence and long-range transport potential

We present the software implementation of The OECD P_OV & LRTP Screening Tool (The Tool) that is used to assess the environmental hazard of organic chemicals using metrics of overall persistence (P_OV) and long-range transport potential (LRTP). The Tool is designed to support decision making for chemical management and includes features that are recommended by the Organization for Economic Cooperation and Development (OECD) expert group on multimedia modeling. The Tool is useful for screening the environmental hazard potential of non-ionizing organic chemicals whose environmental partitioning can be described by absorptive capacities of environmental media estimated from partitioning between air, water and octanol in the laboratory. The software includes data storage functionality, and a user interface that is designed to facilitate simple data input and straightforward interpretation of the model results. The effect of uncertainties in input properties describing chemicals can be assessed with a Monte Carlo analysis. The software is evaluated and illustrated by comparing results from The Tool with those from other models and by evaluating four substances that are candidates for regulation or ban under the Stockholm Convention on Persistent Organic Pollutants.     

Specification‐based testing using cause‐effect graphs

In this paper we discuss the advantages and limitations of a specification‐based software testing technique we call CEG‐BOR. There are two phases in this approach. First, informal software specifications are converted into cause‐effect graphs (CEG). Then, the Boolean OperatoR (BOR) strategy is applied to design and select test cases. The conversion of an informal specification into a CEG helps detect ambiguities and inconsistencies in the specification and sets the stage for design of test cases. The number of test cases needed to satisfy the BOR strategy grows linearly with the number of Boolean operators in CEG, and BOR testing guarantees detection of certain classes of Boolean operator faults. But, what makes the approach especially attractive is that the BOR based test suites appear to be very effective in detecting other fault types. We have empirically evaluated this broader aspect of the CEG‐BOR strategy on a simplified safety‐related real‐time control system, a set of N‐version programs, and on elements of a commercial data‐base system. In all cases, CEG‐BOR testing required fewer test cases than those generated for the applications without the use of CEG‐BOR. Furthermore, in all cases CEG‐BOR testing detected all faults that the original, and independently generated, application test‐suites did. In two instances CEG‐BOR testing uncovered additional faults. Our results indicate that the CEG‐BOR strategy is practical, scalable, and effective across diverse applications. We believe that it is a cost‐effective methodology for the development of systematic specification‐based software test‐suites.     

Replay and testing for concurrent programs

Attention is given to the problems that arise during the testing and debugging cycle of concurrent programs because of their nondeterministic execution behavior, whereby multiple executions of a concurrent program with the same input may exercise different synchronization sequences and even produce different results. These problems are solved by using deterministic execution debugging and testing. The purpose of deterministic execution debugging to to replay executions of a concurrent program so that debugging information can be collected. Examples of semaphores and monitors are used to illustrate the approach and the process of designing replay tubes is described. The use of regression testing to see if earlier debugging and testing introduced new errors, is examined     

Modelling and testing for market volatility

Three types of nonlinear models of volatility of market returns based on the conditional variance models and the logistic and cubic versions of chaotic dynamics are critically reviewed here and empirically tested against three types of market indices: value weighted equally weighted and Standard and Poor's return index for the New York Stock Market. Econometric results provide valuable insights into the temporal variations of the conditional variances and skewness of market returns.     

一种平衡结构性测试和功能性测试的方法

分析了结构性测试和功能性测试方法及其优劣,提出了一种平衡结构性测试和功能性测试的模型方法,即定义-使用测试方法。该方法定义了介于全路径指标和全边之间的测试覆盖指标,提供了一种检查缺陷可能发生点的系统化方法。模拟实例结果表明,定义-使用测试方法能够显著提高发现缺陷的效率。     

Seeking reproducibility: Assessing a multimodal study of the testing effect

Low‐cost devices have widened the use of multimodal data in experiments providing a more complete picture of behavioural effects. However, the accurate collection and combination of multimodal and behavioural data in a manner that enables reproducibility is challenging and often requires researchers to refine their approaches. This paper presents a direct replication of a multimodal wordlist experiment. Specifically, we use a low‐cost Emotiv EPOC® to acquire electrophysiological measures of brain activity to investigate whether retrieval during learning facilitates the encoding of subsequent learning as measured by performance on recall tests and reflected by changes in alpha wave oscillations. Behavioural results of the wordlist experiment were replicated, but physiological results were not. We conclude the paper by highlighting the challenges faced in terms of replicating the previous work and in attempting to facilitate the reproducibility of our own experiment.     

The effect of imperfect error detection on reliability assessmentvia life testing

Measurement of software reliability by life testing involves executing the software on large numbers of test cases and recording the results. The number of failures observed is used to bound the failure probability even if the number of failures observed is zero. Typical analyses assume that all failures that occur are observed, but, in practice, failures occur without being observed. In this paper, we examine the effect of imperfect error detection, i.e. the situation in which a failure of the software may not be observed. If a conventional analysis associated with life testing is used, the confidence in the bound on the failure probability is optimistic. Our results show that imperfect error detection does not necessarily limit the ability of life testing to bound the probability of failure to the very low values required in critical systems. However, we show that the confidence level associated with a bound on failure probability cannot necessarily be made as high as desired, unless very strong assumptions are made about the error detection mechanism. Such assumptions are unlikely to be met in practice, and so life testing is likely to be useful only for situations in which very high confidence levels are not required     

Model-based testing for real

Model-based testing relies on abstract behavior models for test case generation. These models are abstractions, i.e., simplifications. For deterministic reactive systems, test cases are sequences of input and expected output. To bridge the different levels of abstraction, input must be concretized before being applied to the system under test. The systems output must then be abstracted before being compared to the output of the model.The concepts are discussed along the lines of a feasibility study, an inhouse smart card case study. We describe the modeling concepts of the CASE tool AutoFocus and an approach to model-based test case generation that is based on symbolic execution with Constraint Logic Programming.Different search strategies and algorithms for test case generation are discussed. Besides validating the model itself, generated test cases were used to verify the actual hardware with respect to these traces.     

Speeding up the testing and training time for the support vector machines with minimal effect on the performance

The Journal of Supercomputing - Support vector machine faces some problems associated with training time in the presence of large data sets due to the need for high memory and high computational...     

基于气体传感器阵列的易挥发化学品判别系统

利用气体传感器阵列结合判别软件,可用于气体的定性识别。本系统采用气体传感器MQ211组成阵列,结合气室和必要的电路,设计了实时数据采集判别系统,介绍了判别系统的构成与实验过程,实验结果表明:本系统能准确判别多种易挥发化学品。