Assessing the state of software in a large enterprise

To be relevant to the goals of an enterprise, an industrial software engineering research organization must identify problems of interest to, and find solutions that have an impact on, the software development organizations within the company. Using a systematic measurement program both to identify the problems and assess the impact of solutions is key to satisfying this need. Avaya has had such a program in place for about seven years. Every year we produce an annual report known as the State of Software in Avaya that describes software development trends throughout the company and that contains prioritized recommendations for improving Avaya’s software development capabilities. We start by identifying the goals of the enterprise and use the goal-question-metric approach to identify the measures to compute. The result is insight into the enterprise’s problems in software development, recommendations for improving the development process, and problems that require research to solve. We will illustrate the process with examples from the Software Technology Research Department in Avaya Labs whose purpose is to improve the state of software development and know it. “Know it” means that improvement should be subjectively evident and objectively quantifiable. “Know it” also means that one must be skilled at identifying the data sources, performing the appropriate analyses to answer the questions of interest, and validating that the data are accurate and appropriate for the purpose. Examples will include how and why we developed a measure of software quality that appeals to customers, how and why we are studying the effectiveness of distributed software development, and how and why we are helping development organizations to adopt iterative development methods. We will also discuss how we keep the company and the department apprised of the current strengths and weaknesses of software development in Avaya through the publication of the annual State of Software in Avaya Report. Our purpose is both to provide a model for assessment that others may emulate, based on seven years of experience, and to spotlight analyses and conclusions that we feel are common to software development today.     

验证LTE基带接收机

<正> 在传统意义上的无线通信系统中,射频领域的模拟信号可使用模拟技术解调为同相(I)和正交(Q)分量。但在当今软件定义的无线技术时代,中频信号经过变频处理后通常会使用模数转换器(ADC)进行数字化处理,然后再将数字信号馈入基带进行解调和解码。现在,通过将信号发生器的输出频率设为目标中频来生成恰当的中频(IF)信     

Genetic algorithms combined with discriminant analysis for key variable identification

Many trouble-shooting problems in process industries are related to key variable identification for classifications. The contribution charts, based on principal component analysis (PCA), can be applied for this purpose. Genetic algorithms (GAs) have been proposed recently for many applications including variable selection for multivariate calibration, molecular modeling, regression analysis, model identification, curve fitting, and classification. In this paper, GAs are incorporated with Fisher discriminant analysis (FDA) for key variable identification. GAs are used as an optimization tool to determine variables that maximize the FDA classification success rate for two given data sets. GA/FDA is a proposed solution for the variable selection problem in discriminant analysis. The Tennessee Eastman process (TEP) simulator was used to generate the data sets to evaluate the correctness of the key variable selection using GA/FDA, and the T² and Q statistic contribution charts. GA/FDA correctly identifies the key variables for the TEP case studies that were tested. For one case study where the correlation changes in two data sets, the contribution charts incorrectly suggest that the operating conditions are similar. On the other hand, GA/FDA not only determines that the operating conditions are different, but also identifies the key variables for the change. For another case study where many key variables are responsible for the changes in the two data sets, the contribution charts only identifies a fraction of the key variables, while GA/FDA correctly identifies all of the key variables. GA/FDA is a promising technique for key variable identification, as is evidenced in successful applications at The Dow Chemical Company.     

Membrane treatment of side-stream cooling tower water for reduction of water usage

A pilot study was conducted to determine whether membrane treatment on a side stream of recirculating cooling-tower water could reduce overall water usage and discharge. The treated permeate was returned to the cooling tower while the concentrate was discharged to the sanitary sewer. Flow rates, pressures and water chemistry were monitored. The pilot demonstrated potential substantial water savings. Maximum make-up water and discharge reduction were 16% and 49%, respectively. As high as possible permeate recovery is needed to maximize water conservation. Silica scaling on the membranes limited water savings in this pilot. Development of membranes with a solute-rejection capacity less than the 92% average of the membranes used in the pilot would assist in optimizing water savings. Decreased water outlays compensated for the additional energy used by membrane treatment. Scaling control is critical for economic operation.     

Guidelines and recommendations for indoor use of fuel cells and hydrogen systems

Hydrogen energy applications often require that systems are used indoors (e.g., industrial trucks for materials handling in a warehouse facility, fuel cells located in a room, or hydrogen stored and distributed from a gas cabinet). It may also be necessary or desirable to locate some hydrogen system components/equipment inside indoor or outdoor enclosures for security or safety reasons, to isolate them from the end-user and the public, or from weather conditions.Using of hydrogen in confined environments requires detailed assessments of hazards and associated risks, including potential risk prevention and mitigation features. The release of hydrogen can potentially lead to the accumulation of hydrogen and the formation of a flammable hydrogen-air mixture, or can result in jet-fires. Within Hyindoor European Project, carried out for the EU Fuel Cells and Hydrogen Joint Undertaking safety design guidelines and engineering tools have been developed to prevent and mitigate hazardous consequences of hydrogen release in confined environments. Three main areas are considered: Hydrogen release conditions and accumulation, vented deflagrations, jet fires and including under-ventilated flame regimes (e.g., extinguishment or oscillating flames and steady burns). Potential RCS recommendations are also identified.     

Selective decomposition of isopropanol using as prepared and oxidized graphite nanofibers

Three types of as prepared and treated graphite nanofibers (GNFs) were used as catalysts in the decomposition of isopropanol to propene and acetone in the presence of oxygen to evaluate the surface chemistry of the fibers. As prepared herringbone fibers were found to produce higher selectivity for propene compared to the as prepared platelet and ribbon fibers at all temperatures explored. Herringbone fibers that had undergone oxidative treatment with nitric acid, phosphoric acid, ruthenium tetroxide or potassium permanganate were also evaluated at a 290 °C. Effects of oxidation treatments on fiber structure were evaluated using a host of analytical techniques including BET, SEM/EDS, TGA, XPS, and fluorescence labeling of surface species. Selectivity for acetone dehydrogenation product or propene dehydration product could be achieved by the appropriate surface treatment. Nitric acid was the mildest treatment and the treated fibers showed minimal changes. (Potassium permanganate was a harsh treatment that almost completely degraded fiber structure, creating amorphous carbon.) Phosphoric acid treated fibers were found to produce very high conversions and almost pure selectivity for propene. Ruthenium tetroxide did not appear to have a large affect on fiber morphology; however, selectivity for acetone was much higher when GNFs were treated with ruthenium tetroxide.     

Soot oxidation kinetics under pressurized conditions

The oxidation kinetics, under different pressures, of soot samples obtained from different liquid fuels and two standards (a commercial black carbon sample and a reference diesel soot) was studied. Soot samples were generated in a flat-flame, premixed burner under heavily-sooting conditions and captured on a water-cooled stabilization plate located above the burner surface. The collected soot was oxidized using a high-pressure thermogravimetric analyzer (HTGA). TGA operation was optimized to reduce mass transfer effects by adjusting the oxidizer flow rate and initial sample mass. Further corrections for mass transfer were accomplished by computing the effectiveness factors for intraparticle, interparticle, and external mass transfer. Two pressures were evaluated (1 and 10 atm) and O₂ concentration was varied between 10 and 21%.     

Multifunctional glow discharge analyzer for spacecraft monitoring

In this study the main objective was to develop and demonstrate a glow discharge microplasma coupled to a miniature spectrometer for detection of fire signatures from pyrolyzing and burning spacecraft materials. Our experimental results demonstrate that combustion-produced carbonaceous aerosols can serve to identify the burning materials. Demonstrating versatility for chemistry analysis, the plasma detector could differentiate carbonaceous aerosols with different C/H ratios and distinguish inorganic samples such as salts and metal oxides from carbonaceous aerosols. In addition, in situ analysis of aerosol samples validated the microplasma’s analytical utility by linearity of its optical emission intensity with aerosol elemental composition.