Structured Lipids- Increased Protein SynthesisAdvances in the technology behind lipid synthesis led to the development of structured lipids (SLs). A structured lipid (SL) is a triglyceride that includes both medium (8-12 carbons) and long-chain fatty acids (14-22 carbons) within the same triglyceride. Emulsions including SL have demonstrated increased protein synthesis and increased nitrogen balance (NB) in burned animals The SL has also been superior to medium-chain triglyceride (MCT) and long-chain triglyceride (LCT) emulsions in stimulating muscle protein synthesis in animal studies.The use of SLs has been primarily limited to clinical and experimental settings whereby it has become necessary to develop medical nutrition therapies that minimize the adverse effects of high lipid feedings and maximize the positive outcomes. Such positive outcomes include increased protein synthesis, enhanced immune function, decreased risk for cardiovascular disease, and improved glucose homeostasis. The ability to increase protein synthesis, maintain the health of the immune system, and stabilize blood glucose are factors that can also play a role in improving athletic performance. Research on the application of this clinical technology to athletic performance is not available at this time.Peptides- To Provide Glutamine to TPN PatientsIn an effort to provide glutamine to TPN patients in a form that can remain stable in liquid, the amino acid has been bonded with other amino acids, such as the dipeptide alanyl-glutamine. This combination can preserve muscle glutamine levels and muscle protein synthesis after surgery and improve whole-body nitrogen balance. This finding is supported by research on rats with peritonitis Alanylglutamine increased protein synthesis in the liver and skeletal muscle, protected the morphology of the intestinal mucosa, and improved survival in protracted bacterial peritonitis. The researchers concluded that alanylglutamine supplementation may be useful in septic patients.Role of Glutamine as Glucose RegulationThe role of glutamine regarding glucose regulation may be important in exercise-trained individuals. Its function in gluconeogenesis (formation of glucose) and glycogen repletion may serve as a useful function during and after exercise. Gluconeogenesis from glutamine can occur without changes in plasma insulin and glucagon levels, providing evidence that glutamine itself can regulate gluconeogenesis.Nurjhan et al. compared the contribution of alanine and glutamine to glucose formation in postabsorptive (fasted) normal human volunteers and found that the amount of glucose carbon that came from proteinderived glutamine was 100% greater than from alanine. Varnier et al. studied the effects of glutamine, alanine plus glycine, and saline infusion on glycogen accumulation in subjects who cycled for 90 minutes. Two hours postexercise, glutamine infusion resulted in a twofold greater concentration of muscle glycogen than either saline or alanine plus glycine infusion. In postabsorptive humans, glutamine could be more important than alanine for glucose formation derived from proteolysis. Further, glutamine carbon can be directed to glycogen accumulation in skeletal muscle that had been previously glycogen depleted.In mice that were genetically predisposed to being overweight and hyperglycemic, the administration of glutamine in conjunction with a high-fat diet resulted in a reduction of body weight and a drop in hyperglycemia and hyperinsulinemia. The mechanism for a glutamineinduced weight reduction is not known, though it may be related to the ability of glutamine to lessen the insulin resistance induced by a high-fat diet. Further, the administration of glutamine to lipid-based TPN can prevent glucose intolerance and insulin resistance.
Harness the Potential of Technology in the Homebuilding Process
Homebuilders who aren’t interested in offering technology integration as part of their business model are now firmly in the minority. This point is proven by research from the CEA’s annual “State of the Builder Study,” which was compiled in conjunction with the NAHB Research Center. It states that 85 percent of builders believe technology is important in the marketing of a new home. The applications of this technology are extremely compelling to homebuyers: entertainment, whole-home control, security and more that can come with their new house, instead of them hunting for it on the aftermarket.Clearly, in these extremely competitive times, the time is now to embrace technology (if you haven’t already). And thanks to some retrofit technology that’s on the way, it’s effectively yesterday! Allow me to elaborate.Structured wiring and powerline
Wherever possible, structured wiring is a must for the 21st century home, bundling all of the home’s communications wiring into one coherent system. These bundles can include wiring for home networking, telephone, video, audio, alarms, infrared remote control and more. Running these wires before the walls are closed is more cost-effective and less disruptive than ripping up walls to do so at a later date. These bundles also serve as a Trojan horse, giving builders the opportunity to approach the homebuyer with new technological offerings as they become available.Structured wiring has some inherent advantages compared to more slapdash wiring installations. With all of the cables running back to a central wiring panel, it’s easy to change how and what each individual cable is connected to and what it is used for. Structured wiring also makes troubleshooting a snap, since each of the cables can be isolated and tested for problems. Furthermore, because all the cables run back to the central wiring panel, they can all be connected to the same source without the need for some outlets to pass through more splitters and splices than others. This greatly improves the consistency of signals.Structured wiring isn’t a good fit for every builder or every situation, however. With that in mind, here’s some great news. If you’re not willing to commit to structured wiring, a new option that leverages the electrical wiring in a home to transmit audio, data and more is on the horizon. This technology will allow you to retrofit your existing housing inventory at a reasonable cost and with minimal disruption to add a fresh twist for wooing homebuyers. The system will also provide an alternative way to offer some technology to homebuyers if you aren’t yet investing in full-blown structured wiring for new builds. A multi-room audio system using this technology will be available later this year with other solutions certain to follow.The first feasible multi-room audio system using powerline technology will be available later this year with other solutions certain to follow. If you hear the name Renovia in the near future, you now have the inside scoop.Explore Quick and Easy Demos
Demonstrating technology, particularly architectural consumer electronics like multi-room audio, has long been a thorny issue for home builders. A prominent objection is the expense. So consider this inexpensive trick to introduce the multi-room audio concept into your model home at a fraction of the cost of installing a full-fledged multi-room audio system. It starts by utilizing the consumer’s own music with an appliance they know and understand: the iPod.Multi-room audio today is a more compelling new-home option than ever because it ties directly into the exploding concept of “My Music” among consumers. The advent of portable music players like the iPod has enabled music collections to go virtually anywhere their owners go. Many home buyers would welcome the extension of “My Music” to an entire home. By providing a simple music demonstration, you can entice home buyers by showing them how uncomplicated, powerful and fun a multi-room audio system can be.Simply install an amplified source input and connect it to an iPod dock and in-wall or in-ceiling speakers. Set up a location in the room where an on-wall audio control pad would go. You don’t need to install a live control pad, just a blank plate covered with a transparent graphic that shows what a control interface would look like. Install this demo in the most public of spots in the home-the kitchen. Allow the home buyer to plug his or her iPod into the dock and hear the music instantly over the speakers. The demo will show the home buyer how easy it would be to hear “My Music” over the home’s audio system. It will make an immediate “I want that” impact on the home buyer: “Here’s something that will make life in this house simpler and richer.”This unique selling approach is highly affordable. Roughly speaking, a pair of speakers runs $200, an iPod dock runs $49, and an amplified in-wall local source runs $125. Add a nominal cost for speaker wire and installation, and you’ve got a slick demo that doesn’t break the bank.Find Your Digital Path
Believing technology is important, as the aforementioned CEA-NAHB study found, doesn’t make it easy. The complexity of choosing and installing home technology systems and products has always been the biggest hurdle for homebuilders, and it remains so. Low-voltage integration of consumer electronics products requires specialized skills, especially when dealing with proprietary technology platforms, rapidly changing technologies and user preferences, and the unique programming and configuration models many systems employ. Acquiring these skills-either by partnering with a local electronic systems contractor (ESC) or hiring your own talent-can be expensive and time-consuming. The builder just wants it to be profitable.
The current slowdown is giving us all a chance to reconsider, reflect and reboot what we do and how we do it. Right now is the time for the builder to consider this: What kind of technology offerings do my potential homebuyers want? Once you definitively answer that question, you can build a new, updated strategy from there-before you make any investments that may or may not be as focused and efficient as they should be.Homebuyers in 2009 are far more sophisticated about technology than they were even five years ago. Smart phones, multi-room entertainment systems, networked PCs, HDTVs, iPod docks, GPS systems and powerful universal remotes, among other products and concepts, have changed the way homeowners and homebuyers view technology. It’s no longer considered a convenience or a luxury to be “connected.” It’s now a lifestyle necessity. It’s something people expect, and it’s something that can and should be profitable for homebuilders.Identify what homebuyers care most about. Is it security, entertainment, energy management, convenience? A newly married twenty-something couple is probably going to get more excited about streaming music from their iPods all over the house, while a five-person family might want a dedicated home theater for movie nights and the ability to monitor security cameras from any TV in the house. Get a good sense of your target demographic’s needs, and explore and build your technology strategy and options from there.In-House or Partnerships?
One way larger builders are adding technology integration services is by hiring ESCs. These professionals often are members of the Custom Electronics Design and Installation Association (CEDIA), the main trade association for ESCs, which provides them training, certification and education. Both CEDIA and the CEA both offer a wealth of educational information for builders that includes best practices for technology installation.Ideally, every builder would be able to employ one or more in-house ESCs who could control the customer experience and installation process. Unfortunately, not every homebuilder has the resources to expand in this way, so long-term partnerships with reputable ESCs are the next best option.The worst nightmare for a builder is to hire an unfamiliar “tech guy” at the homeowner’s request who comes in, does the electronics and wiring installation, collects his check and is never heard from again. The builder is often left holding the bag, but unfortunately is simply not equipped to troubleshoot any sort of A/V or electronics systems issues. Homeowners don’t want to hear this, however.Before working with any independent ESC, demand that the ESC will be responsible for all follow-up service calls. The builder must be certain that the ESC will provide support over the long haul; if not, the installation should not proceed. By building a strong partnership with an ESC, the builder will gain a loyal and trusted A/V specialist on call who can provide punctual, effective service, rather than always scrambling at the last second to find someone to consult or, even worse, leaving it in the homeowner’s hands. Fortunately, collaboration between CEDIA, CEA and NAHB is at an all-time high and each trade group provides resources for pairing up homebuilders with ESCs on a local level.Involvement early in projects allows the ESC to plan progressively not only with the builder but with the other trades in order to avoid costly and unnecessary changes to wiring, closet/outlet placement and other things that can affect electronics installation and performance.Regardless of whether services are contracted or offered in-house, it’s wise for builders to have an understanding of “good, better, best” technology solutions for their customers. By offering coherent and appealing electronics packages, you can better keep on-time and on-budget. Avoid customization in all but the largest luxury homes, where price is secondary to the homebuyer and the sky is the limit.Whether through an in-house staff or a partnership with an independent ESC, home builders need to find the technology models that work best for them financially and logistically. Ignoring technology is no longer an option when dealing with today’s homebuyers. Fortunately, those of us in the electronics industry are willing and able to help builders get where they need to go. We’re willing and eager to do great work for you-both in your upcoming projects, and to help you sell your existing inventory.
Software Maintenance Implications on Cost and Schedule
Abstract The dictionary defines maintenance as, “The work of keeping something in proper order.” However, this definition does not necessarily fit for software. Software maintenance is different from hardware maintenance because software doesn’t physically wear out, but often gets less useful with age. Software is typically delivered with undiscovered flaws. Therefore, software maintenance is: “The process of modifying existing operational software while leaving its primary functions intact.” Maintenance typically exceeds fifty percent of the systems’ life cycle cost . While software maintenance can be treated as a level of effort activity, there are consequences on quality, functionality, reliability, cost and schedule that can be mitigated through the use of parametric estimation techniques.1. INTRODUCTION One of the greatest challenges facing software engineers is the management of change control. It has been estimated that the cost of change control can be between 40% and 70% of the life cycle costs . Software engineers have hoped that new languages and new process would greatly reduce these numbers; however this has not been the case. Fundamentally this is because software is still delivered with a significant number of defects. Capers Jones estimates that there are about 5 bugs per Function Point created during Development . Watts Humphrey found “… even experienced software engineers normally inject 100 or more defects per KSLOC . Capers Jones says, “A series of studies the defect density of software ranges from 49.5 to 94.5 errors per thousand lines of code .” The purpose of this article is to first review the fundamentals of software maintenance and to present alternative approaches to estimating software maintenance. A key element to note is that development and management decisions made during the development process can significantly affect the developmental cost and the resulting maintenance costs.2. SOFTWARE MAINTENANCE Maintenance activities include all work carried out post-delivery and should be distinguished from block modifications which represent significant design and development effort and supersede a previously released software package. These maintenance activities can be quite diverse, and it helps to identify exactly what post-delivery activities are to be included in an estimate of maintenance effort. Maintenance activities, once defined, may be evaluated in a quite different light than when called simply “maintenance”. Software maintenance is different from hardware maintenance because software doesn’t physically wear out, but software often gets less useful with age and it may be delivered with undiscovered flaws. In addition to the undiscovered flaws, it is common that some number of known defects pass from the development organization to the maintenance group. Accurate estimation of the effort required to maintain delivered software is aided by the decomposition of the overall effort into the various activities that make up the whole process.3. APPROACHING THE MAINTENANCE ISSUE Maintenance is a complicated and structured process. In his textbook, Estimating Software Intensive Systems, Richard Stuzke outlines the typical software maintenance process. It is apparent that the process is more than just writing new code.The following checklist can be used to explore the realism and accuracy of maintenance requirements.o Which pieces of software will be maintained?o How long will the system need to be maintained?o Are you estimating the entire maintenance problem, or just incremental maintenance?o What level of maintenance is required?o Is that which is being called maintenance in fact a new development project?o Who will do the maintenance? Will it be done organically by the original developer? Will there be a separate team? Will there be a separate organization?o Will maintainers be using the same tools used during development? Are any proprietary tools required for maintenance?o How much Commercial-Off-The-Shelf (COTS) is there? How tightly coupled are the interfaces?o Some follow-on development may be disguised as maintenance. This will either inflate maintenance figures, or else cause shortfalls if basic maintenance gets pushed aside. These questions will help you ask whether maintenance is being honestly represented.o Is the activity really an incremental improvement?o Are healthy chunks of the original code being rewritten or changed?o Will additional staff be brought in to perform the upgrade?o Is the maintenance effort schedule regular and fairly flat, or does it contain staffing humps that look like new development?4. SANITY CHECKS Although sanity checks should be sought on a year-by-year basis, they should not be attempted for overall development. The reason for this is that maintenance activities can be carried on indefinitely, rendering any life-cycle rules useless. As an example, consider Grady (p. 17):We spend about 2 to 3 times as much effort maintaining and enhancing software as we spend creating new software.This and similar observations apply at an organizational level and higher, but not for a specific project. Any development group with a history will be embroiled in the long tail ends of their many delivered projects, still needing indefinite attention. Here are a few quick sanity checks:o One maintainer can handle about 10,000 lines per year.o Overall life-cycle effort is typically 40% development and 60% maintenance.o Maintenance costs on average are one-sixth of yearly development costs.o Successful systems are usually maintained for 10 to 20 years.Finally, as in development, the amount of code that is new versus modified makes a difference. The effective size, that is, the equivalent effort if all the work were new code, is still the key input for both development and maintenance cost estimation.5. FIVE ALTERNATIVE APPROACHES All software estimation techniques must be able to model the theory and the likely real world result. The real world scenario is that over time, the overlay of changes upon changes makes software increasingly difficult to maintain and thus less useful. Maintenance effort estimation techniques range from the simplistic level of effort method, through more thoughtful analysis and development practice modifications, to the use of parametric models in order to use historical data to project future needs.5.1 Level of Effort As is sometimes the case in the development environment, software maintenance can be modeled as a level of effort activity. Given the repair category activities and the great variance that they show, this approach clearly has deficiencies. In this approach, a level of effort to maintain software is based on size and type.5.2 Level of Effort Plus Stuzke proposed that software maintenance starts with basic level of effort (minimum people needed to have a core competency and then that that basic core staff must be modified by assessing three additional factors; configuration management, quality assurance, and project management. His process addressed some of the additional factors affecting software maintenance.5.3 Maintenance Change Factor Software Cost Estimation with COCOMO II (Boehm 2000) proposes a deceivingly simple, but also quite useful methodology for determining annual maintenance. Maintenance is one of the menu selections in the menu bar. In COCOMO II Maintenance encompasses the process of modifying existing operational software while leaving its primary functions intact. This process excludes:o Major re-design and re-development (more than 50% new code) of a new software product performing substantially the same functions.o Design and development of a sizeable (more than 20% of the source instructions comprising the existing product) interfacing software package which requires relatively little redesigning of the existing product.o Data processing system operations, data entry, and modification of values in the database.The maintenance calculations are heavily based upon the Maintenance Change Factor (MCF) and the Maintenance Adjustment Factor (MAF). The MCF is similar to the Annual change Traffic in COCOMO81, except that maintenance periods other than a year can be used. The resulting maintenance effort estimation formula is the same as the COCOMO II Post Architecture development model.As stated previously, three cost drivers for maintenance differ from development. Those cost drivers are software reliability, modern programming practices, and schedule. COCOMO II assumes that increased investment in software reliability and use of modern programming practices during software development has a strong positive effect upon the maintenance stage.Annual Maintenance Effort = (Annual Change Traffic) * (Original Software Development Effort)The quantity Original Software Development Effort refers to the total effort (person-months or other unit of measure) expended throughout development, even if a multi-year project.The multiplier Annual Change Traffic is the proportion of the overall software to be modified during the year. This is relatively easy to obtain from engineering estimates. Developers often maintain change lists, or have a sense of proportional change to be required even before development is complete.5.4 Managing Software Maintenance Costs by Developmental Techniques and Management Decisions During DevelopmentWhen it comes to maintenance, “a penny spent is a pound saved.” Better development practices (even if more expensive) can significantly reduce maintenance effort, and reduce overall life cycle cost. The more effort put into development, the less required in maintenance. As an example, the software development cost and schedule can be significantly impacted (reduced) by letting the number of defects delivered grow. This cost and schedule reduction is more than offset by the increase in maintenance cost. The following discussion is an example of how management decision can significantly affect/reduce software maintenance costs.Lloyd Huff and George Novak of Lockheed Martin Aeronautics in their paper “Lockheed Martin Aeronautics Performance Based Software Sustainment for the F-35 Lightning II” propose a series of development and management decision designed to impact and reduce software maintenance costs. They propose an eight step process to estimate and control software maintenance . Their proposed steps are:1. Strive for Commonality2. Apply Industrial Engineering Practices to Software3. Engage4. Adopt a Holistic Approach to Sustainment5. Develop Highly Maintainable Systems and Software6. Manage the Off-the-Shelf Software7. Plan for the Unexpected8. Analyze and Refine the Software Sustainment Business Case (use Parametric software sustainment cost estimates)5.5 A Parametric Assessment of Software MaintenanceParametric models like SEER for Software allow maintenance to be modeled in either of two ways:Estimating maintenance as a part of the total lifecycle cost. Choosing the appropriate Maintenance category parameters will include an estimate of maintenance effort with the development estimate for the individual software program. Several reports and charts show breakdowns of development vs. maintenance effort. This method is best used to evaluate life cycle costs for each individual software program.Estimating maintenance as a separate activity. Using the appropriate maintenance parameters for the software to be maintained you can model the maintenance effort as a separate activity. This method will allow you to fine tune your maintenance estimate by adjusting parameters. Maintenance size should be the same as development size, but should be entered as all pre-existing code. This method can also be useful in breaking out total project maintenance costs from project development costs.A good parametric estimate for maintenance includes a wide range of information. Critical information for completing a software maintenance estimate is the size or amount of software that will be maintained, the quality of that software, the quality and availability of the documentation, and the type or amount of maintenance that will be done. Many organizations don’t actually estimate maintenance costs; they simply have a budget for software maintenance. In this case, a parametric model should be used to compute how much maintenance can actually be performed with the given budget.Estimating and planning for maintenance are critical activities if the software is required to function properly throughout its expected life. Even with a limited budget, a plan can be made to use the resources available in the most efficient, productive manner. Looking at the diagram above, you can see that not only are the multiple inputs that impact the maintenance, but there are several key outputs that provide the information necessary to plan a successful maintenance effort.6. Conclusion The conclusions of this article are:o Software maintenance can be modeled using a simplistic method like Level of Effort Staffing, but this technique has significant drawbacks.o Software maintenance costs can be significantly affected by management decisions during the developmental process.o Software maintenance can be accurately estimated using parametric processes.o Software maintenance is best modeled when development and management decisions are coupled with parametric cost estimation techniques.REFERENCES [1] Software Maintenance Concepts and Practices (second Edition) by Penny Grubb and Armstrong Takang, World Scientific, 2005.[2] Estimating Software Intensive Systems; Richard Stuzke, 2005, Addison-Wesley.[3] Lloyd Huff, George Novak; Lockheed Martin Aeronautics; Lockheed Martin Aeronautics Performance Based Software Sustainment for the F-35 Lightning II.[4] G. Edward Bryan, “CP-6: Quality and Productivity Measures in the 15-Year Life Cycle of an Operating System,” Software Quality Journal 2, 129-144, June 1993.[5] Software Sizing, Estimation, and Risk Management; Daniel D. Galorath, Michael W. Evans, 2006, Auerbach Publications.