Purdue University researchers have designed a predictive thermostat for heat pumps that has been shown to significantly reduce electricity use.

To meet the ambitious environmental goals being proposed at all levels of government, residential air-to-water heat pumps are emerging as a transformative solution to lower carbon emissions, enhance energy efficiency, and reduce utility bills.

What are the most common mistakes in heat pump installs, and how do you avoid them? Here’s what experts had to say about heat pump installation — a must-watch as electrification continues to gain momentum.

Variable-speed heat pumps, which dominate the heat pump market in many countries, are getting more attention in the U.S. The NEWS asked several manufacturers about the benefits of the technology.

All-electric options have come a long way since their inception, and there’s never been a better time to get on board.

“(I’m Your) Heat Pump” is a soft, funky, R&B love song told from the perspective of a heat pump that depicts just what a heat pump can provide to its users.

This new private-public partnership wants to quadruple heat pump installation in California over the next 6 years.

The DOE's new Rooftop Accelerator program encourages manufacturers to develop efficient commercial rooftop heat pumps for cold climates, which could reduce GHG emissions and energy costs by up to 50%.

With “heat pump” and “incentives” almost being synonymous at this point, contractors need to understand the basics to ensure customers are receiving the benefits.

Industry figures are estimates that are derived from the best available figures supplied by a sample of AHRI member companies.

HVAC industry representatives are pushing back on a bid by more than two dozen public interest groups for an eventual ban on new fossil-fuel-burning heating appliances.

If contractors in colder climates focus on educating their customers on what new higher-efficiency furnaces bring to the table, often times the furnaces will sell themselves.

The decision is a win for the California Restaurant Association, which challenged the ban that took effect in 2020. The city has not decided whether to appeal.

Residential gas furnaces must all have a minimum AFUE of 95% beginning in five years. Some in the HVAC industry say the new Department of Energy rule will ultimately hurt homeowners.

Due to a lack of training, time constraints, and numerous other reasons, many HVAC contracting companies are not performing combustion testing, potentially compromising customers’ safety.

U.S. Senator Ted Cruz is leading the charge to assist HVAC contractors in pushing back on the final rule on gas furnace efficiency standards from the U.S. Department of Energy (DOE).

If contractors don’t have a plan in place to handle red tag furnace second opinions, they can expect some mistakes.

A homeowner in Pickering, Ontario works with an experienced HVAC pro to improve comfort, efficiency, and energy savings with a high-efficiency hydronic forced-air furnace upgrade.

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In this episode we talk with Doug Schmidt. Doug is a professor of computer science at Vanderbilt University and a well-respected authority in the fields of middleware, patterns and model-driven development. In this interview we talk about these topics in the context of distributed, realtime embedded (DRE) systems.

In this Episode, Eberhard and Markus provide an introduction to Model-Driven Software Development. Since the discussion turned out to be too long, we separated things into two episodes, thus Episode 6 will be the second part of this discussion. In this first part we disucsss core concepts of MDSD, the relationship to MDA, and hint at a couple of tools.

After discussing some of the more technical aspects of MDSD in the last episode, we take a look at other important topics in this one. This includes some tips on how to introduce MDSD into projects and how the development process has to be adapted for this to work, as well as a look at the return on investment for MDSD. The relationship of MDSD and Agile software development is also discussed. Finally, we take a look at offshoring in the context of MDSD.

Eric Evans is the author of the well known Domain-Driven Design book. In his day job he works as a consultant and coach for his own company, Domain Language. In this interview, Eric talks about the essential building blocks of domain-driven design as well as about a set of best practices on how to address complex projects. In a third part, he elaborates on the relationship of domain-driven design and MDSD/MDA.

In this Episode we have the pleasure of talking with Gregor Kiczales. Gregor is one of the fathers of aspect-oriented programming (AOP). Today he is a professor of computer science at the University of British Columbia. Back in his days at Xerox Parc, he and a number of other people worked on the early forms of AOP as well as on some of its forerunners, such as meta object protocols. In this interview, we talk about a number of interesting topics, such as the history of AOP, the relationship of AO to interceptors, the industry acceptance of AOP, early aspects (i.e. using AO in development phased before implementation) as well as adoption strategies for AOP.

In this Episode we talk to Ted Neward. Since Ted is active in the .NET and Java universes, we started out by discussing some of the differences between the two platforms. The main discussion, however, focussed on new features in the C# 3.0 language. These include LINQ (language-integrated query). A very interesting discussion about extension methods, lamda expression, typing (dynamic, duck, compiler) and other language "tricks" follows. We also visited the topic of language development on the .NET and Java platforms in general, also looking at topics such as concurrency and the Scala language.

A very important area for Java are Enterprise Systems. With the advent of new technologies like Ruby on Rails, Java EE 5 or EJB 3 the landscape for Enterprise Systems appears to be changing a lot at the moment. In this episode Markus talks with Eberhard about what Enterprise Java actually is, why and where it is used. Based on that they discuss what the future might look like and how to make Enterprise Java shine in the future.

In this Episode, we talk to Michael Stal, a Senior Principal Engineer at Siemens Corporate Technology, POSA 1 and 2 Co-Author and Editor of the german JavaSpetrum magazine. Since Michael's core focus is middlware, much of our discussion centered around that topic. Webservices and SOA, of course, have also been covered. Other topics include Java vs. .NET as well as Patterns.

In this episode Arno and Alex talk about the basics of software development processes. They discuss why and when software development processes are needed and also why some developers don't like them. They discuss the theories behind different processes and talk about defined vs empiric processes in general. This episode is the first in a row that will later on describe specific processes like eXtreme programming or the unified process.

In this Episode, Arno, Bernd and Markus interview Jutta Eckstein. Jutta is a pioneer and expert on using Agile software development, specifically in larger teams. In the interview we talk about the agile manifesto, the role of personal relationships and trust in software projects, differences between agility in the small and in the large, as well as offshoring.

SOA (Service Oriented Architecture) appears to be just another hype - after all we have been building distributed systems for quite a while now. But the real value of SOA is non-technical. In this episode Eberhard and Markus discuss the advantages and disadvantages, what SOA actually is and how it compares to other approaches that have been tried out before.

In this, as well as in the next episode Eberhard and Markus continue their discussion about SOA (the episode got too long, so we had to split it into two ... SOA 2a and SOA 2b). In this episode, we talk about the various perspectives on SOA (CBD, EAI, BPM), about fundamental requirements towards an SOA, and we discuss the role of models in defining sustainable architectures. We also discuss how a programming model based on the described approach typically looks like. We then discuss a number of issues any large-scale SOA faces (and for which the SOA paradigm does not really provide an out-of-the-box solution: In this episode we discuss data type ownership and (weak) typing of data types.

This is the second snippet of the SOA 2 double-episode. Eberhard and Markus continue the discussion with the issue of service reuse and a couple of development process issues. We also look at the duality between infrastructure development and application development in the context of an SOA. We then discuss the great spaghetti misunderstanding :-). We conclude this episode with a look at how to integrate BPM into the conceptual SOA framework we've built up to now, and we'll also briefly skim over a number of technologies related to SOA. Note that this episode, as well as the last one, is based on a set of slides; these can be downloaded from here. This episode covers slides 39 through 74.

This episode is an interview with Guy L. Steele Jr.. Guy is a Sun Fellow and heads the Programming Language Research Group within Sun, and a generally well known "programming language guy" (see here for details). We briefly talk about Lisp and the resurgence of dynamic languages before we delve into the main topic, the Fortress programming language he is working on. Fortress is a language intended to replace Fortran as a scientific computing language. We talk about how mathematical notations, syntax extensio and built-in support for parallelism are crucial properties of such a language. We then briefly talk about potentials for compiler optimization before taking a closer look at the type system (static typing, type inference), traits and contract specification as well as first-class support for hierarchical components. We conclude the discussion with a look at automatic partitioning and distribuion of concurrent algorithms and a brief look at the future roadmap for the Fortress language.

Designers, programmers, engineers, we must all return to programming! Very few programmers tend to see their (sometimes rather general) difficulties as the core of the subject and as a result there is a widely held consensus as to what programming is really about. If these notes prove to be a source of recognition or to give you the appreciation that we have simply written down what you already know about the programmer's trade, some of our goals will have been reached.

This episode is an interview with Steve Vinoski. Steve works as the Chief Engineer for IONA. He's what you'd call a middleware guru, he was for example deeply involved with CORBA. So, this interview centers mainly around middleware. We begin by talking about his own history wrt. middleare and ORBs and how ORBs evolved over time. We then talked about whether coarse-grained, stateless components might be a better abstraction for distributed systems than "objects". We then covered the future of CORBA, it's use in ethe embedded space as well as the practical relevance of the POSA patterns when building ORBs. Then we switched topics and addressed the role of web services as a "middleware middleware" and the maturity of WS-* specifications. We then looked at what Steve is working on these days, which is e.g. the Advanced Message Queueing Protocol (AMQP) as well as dynamic languages. We concluded the interwiew with his view on SOA.

This episode is an interview with Werner Vogels, the CTO of amazon.com. We first talked about what scalability is, and which aspects there are to scalability. We then took a brief look at the technologies used at amazon, specifically, the middleware systems and the issue of vendor lock-in. Web services, and the role of SOA was the next topic. Then we covered what a service actually is add Werner explained the term "pizza teams". Testing and Deployment was the next topic followed by a look at architectural characteristics of scalable systems, the value of simplicity and the CAP theorem. We concluded the discussion with a brief look at the future of distributed systems

In this episode, Gregor Hohpe gives us a great introduction to enterprise messaging based on his EAI Patterns book. Before we started discusssing the patterns in his book, we characterized messaging and talked about the various interaction styles. We also contrasted the messaging architectural style with an RPC based approach. We then took a look at the relationship to SOA, the role of contracts and the orchestration-vs-choreography discussion. We briefly discussed the nature of pattern languages before we then went through the different section in the book. There are six main sections: channel, message, routing, transfomation, endpoint as well as management and monitoring. We discussed the core patterns for each of these sections. This should give listeners a good high-level view of message-based systems. We concluded the discussion by looking at the critical importance of systems management and monitoring.

This is another episode on concurrency. We talk to two experts in the field, Brian Goetz and David Holmes about aspects of concurrency we hadn't really covered before. We start out by discussing liveness and safety and then continue to talk about synchronizers (latches, barriers, semaphores) as well as the importance of agreeing on protocols when developing concurrent applications. We then talked about thread confinement as a way of building thread-safe programs, as well as using functional programming and immutable data. The next set of topics covers various ways of how compilers can optimize the performance wrt. to concurrency, talking about techniques such as escape analysis as well as lock elision and coarsening. We then covered how to test concurrent programs and the consequences of the Java memory model on concurrency. We then went on to look at some more advanced topics, namely, lock-free programming and atomic variables. We also briefly discussed the idea of transactional memory. Finally, we looked at how better language support - specifically, a more declarative style of concurrent programming as e.g. in the Fortress language - can aid in improving the quality of concurrent programs.

In this Episode we are happy to talk to Grady Booch. We started off by discussing his Architecture Handbook, how it came into being, the progress, and how it will look like once it's finished. In this context we also looked at the issue of how to distinguish architecture from design. We then asked him about how "professional" software architecture is these days, as well as about the ubiquity of software product lines in industry. The next couple of minutes looked at the question of whether software development is an engineering discipline, craftsmanship or an art form, and we discussed the key qualifications of software developers. Grady then elaborated on the problems of developing in large teams as well as the potential limits of complexity we can tackle with software.

We then got back to a more technical discussion, where we looked at model-driven development, DSLs, etc. and the role of the UML in that context. Next was a discussion about scripting languages, and the current trend towards new languages. We then looked at component marketplaces and other forms of reuse, as well as the importance of OO these days and the relevance of AO. We concluded with a (small) outlook to the future.

In this Episode we discuss software architecture evaluation with Dragos Manolescu, an architect at Microsoft's patterns & practices group.

We start off the discussion by trying to define what software architecture evaluation is and when and you want to evaluate an architecture in the system's lifecycle. We then make sure evaluators set the expectations for the evaluation process right - it is important to understand that architecture evaluation is typically not primarily a review of the technology decisions made for the architecture.

We then discuss the kinds of notations that are useful for describing architectures, and which of these are especially helpful for the evaluator. Next we look at the core of the architecture evaluation task, namely, the integration of the various stakeholders and their views. We also discuss real reviews from reviews that are staged "for show" only.

Next in the discussion is a brief look at the tools you can use for architecture evaluation, as well as a closer look at the various methods for achitecture evalualtion proposed by the Software Engineering Institute (SEI). We conclude the discussion by outlining how architecture evaluation fits into an agile development process.

... and finally, we briefly plug the PLOPD5 book, on which Dragos, Markus and James Noble have been working recently :-)

In this episode, we're talking to Obie Fernandez about agile DSL development in Ruby. We started our discussion by defining what a DSL is, the difference between internal and external DSLs as well as the importance of the flexibly syntax of the host language in order to make DSLs worthwhile. We then looked at a couple of real world examples for DSLs, specifically, at Business Natural Languages. We then progressed to the main part of the discussions, which centered around the features of Ruby that are important for building DSLs. These include the flexible handling of parentheses, symbols, blocks as well as literal arrays and hashes. We then discussed Ruby's meta programming feautures and how they are important for building DSLs: instantiation, method_missing callback, class macros, top level functions and sandboxing. Features like eval, class_eval, instance_eval and define_method are also important for DSLs in Ruby, as well as using alias_method for simple AOP.

This episode is an interview with Frank Buschmann, one of the pioneers of the pattern movement in Europe. Michael and Frank discuss how it all began: the first conferences on patterns and the first publications by the Gang-of-Four and the POSA 1 team. Frank then elaborates on the new volumes in the Pattern-Oriented Software Architecture book series - POSA 4 and POSA 5 - and gives some examples from the books. The episode concludes with a general discussion on software design and architecture, and best practices on software development.

In this Episode I talk about the results of the listener survey and reply to some of the suggestions and criticism expressed in survey replies.

This episode is about OSGi, the dynamic module system for Java. Our guests are Peter Kriens (OSGI's Technical Director) and BJ Hargrave (OSGI's CTO). We'll discuss what OSGi is all about and why and in which contexts it is useful. Additionally we are having a look at the different layers of OSGI and where and how they are used. Other questions discussed are: What means dynamicity in an OSGI environment? Where is OSGI used? What’s the future of OSGI? How does OSGI interact with existing middleware solutions? How can I run several versions of the same JAR at the same time? Where are OSGI’s problems?