Abstract: Interpreting compiler errors and exception messages is challenging for novice programmers. Presenting examples of how other programmers have corrected similar errors may help novices understand and correct such errors. This paper introduces HelpMeOut, a social recommender system that aids the debugging of error messages by suggesting solutions that peers have applied in the past. HelpMeOut comprises IDE instrumentation to collect examples of code changes that fix errors; a central database that stores fix reports from many users; and a suggestion interface that, given an error, queries the database for a list of relevant fixes and presents these to the programmer. We report on implementations of this architecture for two programming languages. An evaluation with novice programmers found that the technique can suggest useful fixes for 47% of errors after 39 person-hours of programming in an instrumented environment.

Abstract: Cosponsored by 4D Technology (United States) • Andor Technology, Ltd. (United Kingdom) • Astronomical Consultants & Equipment, Inc. (United States) • Giant Magellan Telescope (Chile) • GPixel, Inc. (China) • Harris Corporation (United States) • Materion Corporation (United States) • Optimax Systems, Inc. (United States) • Princeton Infrared Technologies (United States) • Symétrie (France) •Teledyne Technologies, Inc. (United States) • Thirty Meter Telescope (United States)

Abstract: Binary instrumentation facilitates the insertion of additional code into an executable in order to observe or modify the executable's behavior. There are two main approaches to binary instrumentation: static and dynamic binary instrumentation. In this paper we present a static binary instrumentation toolkit for Linux on the x86/x86_64 platforms, PEBIL (PMaC's Efficient Binary Instrumentation Toolkit for Linux). PEBIL is similar to other toolkits in terms of how additional code is inserted into the executable. However, it is designed with the primary goal of producing efficient-running instrumented code. To this end, PEBIL uses function level code relocation in order to insert large but fast control structures. Furthermore, the PEBIL API provides tool developers with the means to insert lightweight hand-coded assembly rather than relying solely on the insertion of instrumentation functions. These features enable the implementation of efficient instrumentation tools with PEBIL. The overhead introduced for basic block counting by PEBIL is an average of 65% of the overhead of Dyninst, 41% of the overhead of Pin, 15% of the overhead of DynamoRIO, and 8% of the overhead of Valgrind.

Abstract: Large scale active measurement of the Internet requires appropriate software support. The better tools that we have for executing consistent and systematic measurements, the more confidence we can have in the results. This paper presents scamper, a powerful open-source packet-prober for active measurement of the Internet designed to stand alone from coordination mechanisms. We built scamper and populated it with specific measurement techniques, making design decisions aimed at allowing Internet researchers to focus on scientific experiments rather than building accurate instrumentation.

Abstract: Moisture assays can be one of the most important analyses performed on a food product and yet one of the most difficult from which to obtain accurate and precise data, for reasons described in this chapter. The first sections of this chapter describe both direct and indirect methods for moisture content analysis: instrumentation, principles, procedures, applications, cautions, advantages, and disadvantages. The choice of moisture analysis method is often determined by the expected moisture content, nature of other food constituents (e.g., highly volatile, heat sensitive), equipment available, speed necessary, accuracy and precision required, and intended purpose (e.g., regulatory or in-plant quality control). Latter parts of this chapter describe water activity measurement, since it parallels the measurement of total moisture as an important stability and quality factor. Determining both the water content and the water activity of a food provides a complete moisture analysis. Also included in the chapter is a major section on moisture sorption isotherms. With an understanding of the techniques described in this chapter, one can apply appropriate moisture analyses to a wide variety of food products.

Abstract: Software instrumentation provides the means to collect information on and efficiently analyze parallel programs. Using Pin, developers can build tools to detect and examine dynamic behavior including data races, memory system behavior, and parallelizable loops. Pin is a software system that performs runtime binary instrumentation of Linux and Microsoft Windows applications. Pin's aim is to provide an instrumentation platform for building a wide variety of program analysis tools, called pintools. By performing the instrumentation on the binary at runtime, Pin eliminates the need to modify or recompile the application's source and supports the instrumentation of programs that dynamically generate code.

Abstract: The new era of software signal processing has a large impact on radio astronomy instrumentation. Our design and implementation of a 32 antennae, 33 MHz, dual polarization, fully real-time software backend for the GMRT, using only off-the-shelf components, is an example of this. We have built a correlator and a beamformer, using PCI-based ADC cards and a Linux cluster of 48 nodes with dual gigabit inter-node connectivity for real-time data transfer requirements. The highly optimized compute pipeline uses cache efficient, multi-threaded parallel code, with the aid of vectorized processing. This backend allows flexibility in final time and frequency resolutions, and the ability to implement algorithms for radio frequency interference rejection. Our approach has allowed relatively rapid development of a fairly sophisticated and flexible backend receiver system for the GMRT, which will greatly enhance the productivity of the telescope. In this paper we describe some of the first lights using this software processing pipeline. We believe this is the first instance of such a real-time observatory backend for an intermediate sized array like the GMRT.

Abstract: Dependencies among system components are crucial to locating root errors in a distributed system. In this paper, we propose an approach to mine intercomponent dependencies from unstructured logs. The technique requires neither additional system instrumentation nor any application specific knowledge. In the approach, we first parse each log message into its log key and parameters. Then, we find dependent log key pairs belong to different components by leveraging co-occurrence analysis and parameter correspondence. After that, we use Bayesian decision theory to estimate the dependency direction of each dependent log key pair. We further apply time delay consistency to remove false positive detections. Case studies on Hadoop show that the technique successfully identifies the dependencies among the distributed system components.

Abstract: A system and method for analyzing and/or testing member devices in a multi-device system. The multi-device system includes a device-under-analysis (DUA) and a device-under-observation (DUO). An analyzer that is external to the multi-device system generates and sends test messages to the DUA. The analyzer monitors the health of the multi-device system through the DUO and detects a system-wide impact of the DUA caused by the test messages. The analyzer analyzes the DUA based on the test messages and the system-wide impact.

Abstract: This paper presents GOOFI-2, a comprehensive fault injection tool for experimental dependability assessment of embedded systems. The tool includes a large number of extensions and improvements over its predecessor, GOOFI. These include support for three widely used fault injection techniques, two target processors, and a variety of new features for storing, disseminating and analyzing experimental data. We report on our experiences and lessons learned from the use and development of GOOFI-2. In particular, we compare and discuss properties of three fault injection techniques: Nexus-based, exception-based and instrumentation-based injection. The comparison relies on several sets of experiments with two target processors, Freescale's MPC565 and MPC5554.

Abstract: This article reviews the main parts of a software-defined radio (SDR) to emphasize several possible implementations of both receivers and transmitters. We describe solutions for testing and characterizing these types of devices. SDRs typically operate in both the analog and the digital domains, thus mixed-domain instrumentation is necessary to carry out testing. We first give a short overview of several architectures for SDR receiver front ends. Then, several possible architectures for transmitter front ends are described. We discuss methods that can be used to improve amplifier efficiency. Instrumentation currently available in the commercial market that allows the characterization of such types of transceivers is presented.

Abstract: Feedback-directed optimization (FDO) is effective in improving application runtime performance, but has not been widely adopted due to the tedious dual-compilation model, the difficulties in generating representative training data sets, and the high runtime overhead of profile collection. The use of hardware-event sampling to generate estimated edge profiles overcomes these drawbacks. Yet, hardware event samples are typically not precise at the instruction or basic-block granularity. These inaccuracies lead to missed performance when compared to instrumentation-based FDO@. In this paper, we use multiple hardware event profiles and supervised learning techniques to generate heuristics for improved precision of basic-block-level sample profiles, and to further improve the smoothing algorithms used to construct edge profiles. We demonstrate that sampling-based FDO can achieve an average of 78% of the performance gains obtained using instrumentation-based exact edge profiles for SPEC2000 benchmarks, matching or beating instrumentation-based FDO in many cases. The overhead of collection is only 0.74% on average, while compiler based instrumentation incurs 6.8%-53.5% overhead (and 10x overhead on an industrial web search application), and dynamic instrumentation incurs 28.6%-1639.2% overhead.

Abstract: Instruction-set randomization (ISR) is a technique based on randomizing the "language" understood by a system to protect it from code-injection attacks. Such attacks were used by many computer worms in the past, but still pose a threat as it was confirmed by the recent Conficker worm outbreak, and the latest exploits targeting some of Adobe's most popular products. This paper presents a fast and practical implementation of ISR that can be applied on currently deployed software. Our solution builds on a binary instrumentation tool to provide an ISR-enabled execution environment entirely in software. Applications are randomized using a simple XOR function and a 16-bit key that is randomly generated every time an application is launched. Shared libraries can be also randomized using separate keys, and their randomized versions can be used by all applications running under ISR. Moreover, we introduce a key management system to keep track of the keys used in the system. To the best of our knowledge we are the first to apply ISR on truly shared libraries.Finally, we evaluate our implementation using real applications including the Apache web server, and the MySQL database server. For the first, we show that our implementation has negligible overhead (less than 1%) for static HTML loads, while the overhead when running MySQL can be as low as 75%. We see that our system can be used with little cost with I/O intensive network applications, while it can also be a good candidate for deployment with CPU intensive applications, in scenarios where security outweighs performance.

Abstract: Introduction Single-port or single-incision cholecystectomy with current rigid laparoscopic devices is limited by in-line visualization, restricting the ability to approach the surgical site with proper angles and instrumentation. A single-port access system with articulating arms and strong instrumentation should minimize these issues. The TransEnterix system may facilitate safe and straightforward single-port surgery.

Abstract: Modern scientific collaborations have opened up the opportunity of solving complex problems that involve multi-disciplinary expertise and large-scale computational experiments. These experiments usually involve large amounts of data that are located in distributed data repositories running various software systems, and managed by different organisations. A common strategy to make the experiments more manageable is executing the processing steps as a workflow. In this paper, we look into the implementation of fine-grained data-flow between computational elements in a scientific workflow as streams. We model the distributed computation as a directed acyclic graph where the nodes represent the processing elements that incrementally implement specific subtasks. The processing elements are connected in a pipelined streaming manner, which allows task executions to overlap. We further optimise the execution by splitting pipelines across processes and by introducing extra parallel streams. We identify performance metrics and design a measurement tool to evaluate each enactment. We conducted experiments to evaluate our optimisation strategies with a real world problem in the Life Sciences---EURExpress-II. The paper presents our distributed data-handling model, the optimisation and instrumentation strategies and the evaluation experiments. We demonstrate linear speed up and argue that this use of data-streaming to enable both overlapped pipeline and parallelised enactment is a generally applicable optimisation strategy.

Abstract: Perhaps surprisingly, no practical performance models exist for popular (and complex) client applications such as Adobe's Creative Suite, Microsoft's Office and Visual Studio, Mozilla, Halo 3, etc. There is currently no tool that automatically answers program developers', IT administrators' and end-users' simple what-if questions like "what happens to the performance of my favorite application X if I upgrade from Windows Vista to Windows 7?". This paper describes our approach towards constructing practical, versatile performance models to address this problem. The goal is to have these models be useful for application developers to help expand application testing coverage and for IT administrators to assist with understanding the performance consequences of a software, hardware or configuration change.This paper's main contributions are in system building and performance modeling. We believe we have built applications that are easier to model because we have proactively instrumented them to export their state and associated metrics. This application-specific monitoring is always on and interesting data is collected from real, "in-the-wild" deployments. The models we are experimenting with are based on statistical techniques. They require no modifications to the OS or applications beyond the above instrumentation, and no explicit a priori model on how an OS or application should behave. We are in the process of learning from models we have constructed for several Microsoft products, including the Office suite, Visual Studio and Media Player. This paper presents preliminary findings from a large user deployment (several hundred thousand user sessions) of these applications that show the coverage and limitations of such models. These findings pushed us to move beyond averages/means and go into some depth into why client application performance has an inherently large variance.

Abstract: These recommendations cover acceptance and reference tests that should be performed for acceptance testing of instrumentation used within a nuclear medicine department. These tests must be performed after installation and before the instrument is put into clinical use, and before final payment for the device. These recommendations must be considered in the light of any national guidelines and legislation, which must be followed. The recommendations cover the types of test to be performed, but they do not specify the procedures to be followed, which are available from other reference sources quoted. Acceptance testing is extremely important, as it can affect the whole life performance of a system. The requirement that acceptance testing be performed should be included in the purchase agreement of an instrument. This agreement should specify responsibilities regarding who does acceptance testing, the procedure to be followed when unsatisfactory results are obtained, and who supplies the required phantoms and software. A specific time slot must be allocated for performing acceptance tests.

Abstract: A dynamic instrumentation system is described herein that performs dynamic, in-memory software code instrumentation achieved by injecting a library into the process to intercept module loads and instrument the methods in those modules with appropriate probes. The system instruments original methods to redirect execution to new methods to perform code verification tasks. By performing dynamic instrumentation, no binaries are modified on-disk, any existing code signing is preserved, and the locations from which the binaries are loaded do not matter. The system allows instrumentation to occur on any computing device, without pre-preparation by a tester or developer to install instrumented binaries. The system also does not involve gaining access to potentially sensitive locations on disk, as the binaries are modified in memory with the originals still unchanged on disk. Thus, the dynamic instrumentation system allows for more effective code analysis with less preparation and hassle for code developers.

Abstract: The main issue of the paper concerns the way new technologies (TI-Nspire and TI-Navigator) influence the different students’ multimodal production, in terms of words, gestures, inscriptions, and actions on the artefacts. Specifically, it investigates how they can modify students’ processes of mathematics learning, what descriptors are the most suitable for grasping such changes, and what are the new opportunities for the teacher in designing and managing mathematical activities within such environments. Three different lenses (instrumentation, humans-with-media, multimodality) are used to analyse some classroom activities, where students employ such new technologies. It is also shown how the multi-representations present in the two technological environments can support the students’ multimodal production, interaction, and communication, when they are engaged in constructing mathematical meanings. In particular, the article underlines new features of the “new technologies”, such as handheld environments, compared with the older ones.

Abstract: Providing a complete introduction to the state-of-the-art in high-speed digital testing with automated test equipment (ATE), this practical resource is the first book focus exclusively on this increasingly important topic Featuring clear examples, this one-stop reference covers all critical aspects of the subject, from high-speed digital basics, ATE instrumentation for digital applications, and test and measurements, to production testing, support instrumentation and text fixture design This in-depth volume also discusses at advanced ATE topics, such as multiplexing of ATE pin channels and testing of high-speed bi-directional interfaces with fly-by approaches

Abstract: Over the last few years, the analysis of seismic noise recorded by two dimensional arrays has been confirmed to be capable of deriving the subsoil shear-wave velocity structure down to several hundred meters depth. In fact, using just a few minutes of seismic noise recordings and combining this with the well known horizontal-to-vertical method, it has also been shown that it is possible to investigate the average one dimensional velocity structure below an array of stations in urban areas with a sufficient resolution to depths that would be prohibitive with active source array surveys, while in addition reducing the number of boreholes required to be drilled for site-effect analysis. However, the high cost of standard seismological instrumentation limits the number of sensors generally available for two-dimensional array measurements (i.e., of the order of 10), limiting the resolution in the estimated shear-wave velocity profiles. Therefore, new themes in site-effect estimation research by two-dimensional arrays involve the development and application of low-cost instrumentation, which potentially allows the performance of dense-array measurements, and the development of dedicated signal-analysis procedures for rapid and robust estimation of shear-wave velocity profiles. In this work, we present novel low-cost wireless instrumentation for dense two-dimensional ambient seismic noise array measurements that allows the real–time analysis of the surface-wavefield and the rapid estimation of the local shear-wave velocity structure for site response studies. We first introduce the general philosophy of the new system, as well as the hardware and software that forms the novel instrument, which we have tested in laboratory and field studies.

Abstract: With the evolution of high-performance computing toward heterogeneous, massively parallel systems, parallel applications have developed new checkpoint and restart necessities. Whether due to a failure in the execution or to a migration of the application processes to different machines, checkpointing tools must be able to operate in heterogeneous environments. However, some of the data manipulated by a parallel application are not truly portable. Examples of these include opaque state (e.g. data structures for communications support) or diversity of interfaces for a single feature (e.g. communications, I-O). Directly manipulating the underlying ad hoc representations renders checkpointing tools unable to work on different environments. Portable checkpointers usually work around portability issues at the cost of transparency: the user must provide information such as what data need to be stored, where to store them, or where to checkpoint. CPPC (ComPiler for Portable Checkpointing) is a checkpointing tool designed to feature both portability and transparency. It is made up of a library and a compiler. The CPPC library contains routines for variable level checkpointing, using portable code and protocols. The CPPC compiler helps to achieve transparency by relieving the user from time-consuming tasks, such as data flow and communications analyses and adding instrumentation code. This paper covers both the operation of the CPPC library and its compiler support. Experimental results using benchmarks and large-scale real applications are included, demonstrating usability, efficiency, and portability. Copyright © 2009 John Wiley & Sons, Ltd.

Abstract: We review approaches for extending the depth of focus of different imaging systems including the human vision system. Approaches involving digital postprocessing as well as different types of all-optical techniques are discussed. C 2010 Society of Photo-Optical Instrumentation

Abstract: Software instrumentation is a powerful and flexible technique for analyzing the dynamic behavior of programs. By inserting extra code in an application, it is possible to study the performance and correctness of programs and systems. Pin is a software system that performs run-time binary instrumentation of unmodified applications. Pin provides an API for writing custom instrumentation, enabling its use in a wide variety of performance analysis tasks such as workload characterization, program tracing, cache modeling, and simulation. Most of the prior work on instrumentation systems has focused on executing Unix applications, despite the ubiquity and importance of Windows applications. This paper identifies the Windows-specific obstacles for implementing a process-level instrumentation system, describes a comprehensive, robust solution, and discusses some of the alternatives. The challenges lie in managing the kernel/application transitions, injecting the runtime agent into the process, and isolating the instrumentation from the application. We examine Pin's overhead on typical Windows applications being instrumented with simple tools up to commercial program analysis products. The biggest factor affecting performance is the type of analysis performed by the tool. While the proprietary nature of Windows makes measurement and analysis difficult, Pin opens the door to understanding program behavior.

Abstract: To build an Electrical Bioimpedance (EBI) spectrometer using the Impedance Measurement System-On-Chip AD5933 together with a 4-Electrode Analog Front End (4E-AFE) has been proven practicable. Such ...

Abstract: Software instrumentation is a key technique in many stages of the development process. It is particularly important for debugging embedded systems. Instrumented programs produce data traces which enable the developer to locate the origins of misbehaviors in the system under test. However, producing data traces incurs runtime overhead in the form of additional computation resources for capturing and copying the data. The instrumentation may therefore interfere with the system's timing and perturb its behavior. In this work, we propose an instrumentation technique for applications with temporal constraints, specifically targeting background/foreground or cyclic executive systems. Our framework permits reasoning about space and time and enables the composition of software instrumentations. In particular, we propose a definition for trace reliability, which enables us to instrument real-time applications which aggressively push their time budgets. Using the framework, we present a method with low perturbation by optimizing the number of insertion points and trace buffer size with respect to code size and time budgets. Finally, we apply the theory to two concrete case studies: we instrument the OpenEC firmware for the keyboard controller of the One Laptop Per Child project, as well as an implementation of a flash file system.

Abstract: Instruction set simulators (Iss) are vital tools for compiler and processor architecture design space exploration and verification. State-of-the-art simulators using just-in-time (Jit) dynamic binary translation (Dbt) techniques are able to simulate complex embedded processors at speeds above 500 Mips. However, these functional Iss do not provide microarchitectural observability. In contrast, low-level cycle-accurate Iss are too slow to simulate full-scale applications, forcing developers to revert to FPGA-based simulations. In this paper we demonstrate that it is possible to run ultra-high speed cycle-accurate instruction set simulations surpassing FPGA-based simulation speeds. We extend the Jit Dbt engine of our Iss and augment Jit generated code with a verified cycle-accurate processor model. Our approach can model any microarchitectural configuration, does not rely on prior profiling, instrumentation, or compilation, and works for all binaries targeting a state-of-the-art embedded processor implementing the ARCompact™ instruction set architecture (Isa). We achieve simulation speeds up to 63 Mips on a standard x86 desktop computer, whilst the average cycle-count deviation is less than 1.5% for the industry standard Eembc and Core Mark benchmark suites.

Abstract: This paper presents a review, based on the published literature and on the authors’ own research, of the current state of the art of fiber-optic capillary sensors and related instrumentation as well as their applications, with special emphasis on point-of-care chemical and biochemical sensors, systematizing the various types of sensors from the point of view of the principles of their construction and operation. Unlike classical fiber-optic sensors which rely on changes in light propagation inside the fiber as affected by outside conditions, optical capillary sensors rely on changes of light transmission in capillaries filled with the analyzed liquid, which opens the possibility of interesting new applications, while raising specific issues relating to the construction, materials and instrumentation of those sensors.