Robert Heinrich

A new, quantitative architecture simulation approach to software design that circumvents costly testing cycles by modeling quality of service in early design states. Too often, software designers lack an understanding of the effect of design decisions on such quality attributes as performance and reliability. This necessitates costly trial-and-error testing cycles, delaying or complicating rollout. This book presents a new, quantitative architecture simulation approach to software design, which allows software engineers to model quality of service in early design stages. It presents the first simulator for software architectures, Palladio, and shows students and professionals how to model reusable, parametrized components and configured, deployed systems in order to analyze service attributes. The text details the key concepts of Palladio's domain-specific modeling language for software architecture quality and presents the corresponding development stage. It describes how quality information can be used to calibrate architecture models from which detailed simulation models are automatically derived for quality predictions. Readers will learn how to approach systematically questions about scalability, hardware resources, and efficiency. The text features a running example to illustrate tasks and methods as well as three case studies from industry. Each chapter ends with exercises, suggestions for further reading, and "takeaways" that summarize the key points of the chapter. The simulator can be downloaded from a companion website, which offers additional material. The book can be used in graduate courses on software architecture, quality engineering, or performance engineering. It will also be an essential resource for software architects and software engineers and for practitioners who want to apply Palladio in industrial settings.

In the 1980s, Willis McGlascoe Carter's handwritten memoir turned up unexpectedly in the hands of a midwestern antiques dealer. Its twenty-two pages told a fascinating story of a man born into slavery in Virginia who, at the onset of freedom, gained an education, became a teacher, started a family, and edited a newspaper. Even his life as a slave seemed exceptional: he described how his owners treated him and his family with respect, and he learned to read and write. Tucked into its back pages, the memoir included a handwritten tribute to Carter, written by his fellow teachers upon his death. Robert Heinrich and Deborah Harding's From Slave to Statesman tells the extraordinary story of Willis M. Carter's life. Using Carter's brief memoir--one of the few extant narratives penned by a former slave--as a starting point, Heinrich and Harding fill in the abundant gaps in his life, providing unique insight into many of the most important events and transformations in this period of southern history. Carter was born a slave in 1852. Upon gaining freedom after the Civil War, Carter, like many former slaves, traveled in search of employment and education. He journeyed as far as Rhode Island and then moved to Washington, DC, where he attended night school before entering and graduating from Wayland Seminary. He continued on to Staunton, Virginia, where he became a teacher and principal in the city's African American schools, the editor of the Staunton Tribune, a leader in community and state civil rights organisations, and an activist in the Republican Party. Carter served as an alternate delegate to the 1896 Republican National Convention, and later he helped lead the battle against Virginia's new state constitution, which white supremacists sought to use as a means to disenfranchise blacks. As part of that campaign, Carter traveled to Richmond to address delegates at the constitutional convention, serving as chairman of a committee that advocated voting rights and equal public education for African Americans. Although Carter did not live to see Virginia adopt its new Jim Crow constitution, he died knowing that he had done all in his power to stop it. From Slave to Statesman fittingly resurrects Carter's all-but-forgotten story, adding immeasurably to our understanding of the journey that he and men like him took out of slavery into a world of incredible promise and powerful disappointment.

Business processes and information systems mutually affect each other in non-trivial ways. Frequently, processes are designed without taking the systems’ impact into account, and vice versa. Missing alignment at design-time results in quality problems at run-time. Robert Heinrich gives examples from research and practice for an integrated design of process and system quality. A quality reference-model characterizes process quality and a process notation is extended to operationalize the model. Simulation is a powerful means to predict the mutual quality impact, to compare design alternatives, and to verify them against requirements. The author describes two simulation approaches and discusses interesting insights on their application in practice.