With increased electronics content, increasingly connected cars, and computers taking more and more control in vehicles, it is only logical that instrument clusters massively change their appearance and functions.
Traditional instrument clusters are a key element of cars that are undergoing substantial changes. The time has arrived for an evolution in traditional main vehicle instrument cluster units. Between the group of mechanical instrument clusters and the growing group of free programmable clusters there is actually the huge area of hybrid dashboards, which combines traditional meters and at least one graphical display for driver information.
With the increasing number of electronic systems in cars, such as driver assistance systems, the number of information and status signals offered to the driver is increasing in parallel. Undoubtedly pictures and graphics can be grasped more easily and quickly by humans than written or digital information. The consequence is a strong trend towards displays within easy view of the driver, mostly as part of a hybrid cluster, but also—as a logical step—implemented as head-up displays (HUDs).
For the automotive industry the design of the driver's environment is a major differentiator from competitors, especially considering the difficult conditions for implementing advanced electronic systems in the car. Quality, robustness, functional safety, data security, low power consumption, etc, are the main criteria. From the cost perspective this means that display and semiconductor technologies have to be available at reasonable prices and have to offer the right amount of scalability in several key areas, such as LCD and TFT, graphics processors and controller units, sensors and LED modules.
New features and applications, with obvious possibilities for integration into instrument clusters, are being introduced into cars via entertainment, navigation, advanced driver assist systems (ADAS), and diagnostic systems. Although multi-purpose head units will still have the main display capability, clusters will be able to offer an auxiliary screen to the driver—especially for multimedia content, even if it were only to access main vehicle information and safety data from ADAS.
Information is shared by www.irvs.info
Thursday, July 21, 2011
Monday, July 18, 2011
Exposing the hidden costs of using off-the-shelf analog ICs
An ASIC does not necessarily have to be a custom integrated circuit. There are many standard analog chips in the market that are simply priced too high. It may make good economic sense to consider using an analog ASIC company developed a chip that mimics a standard product.
Analog ASICs are not for everyone. Like any component choice, they must offer the best economic value for the application. Any associated up-front NRE costs (non-recurring engineering) must be factored into the equation along with hard tooling (wafer fabrication masks, test hardware and software and more). In addition, there is the issue of time. Analog ASICs can take from six months up to a year or more to be ready to use in a production environment. And of course, there is a minimum quantity that must be consumed to assure the value is received. These must all align properly to justify development of an Analog ASIC
Why do Standard Analog ICs Cost So Much?
No one designs and tools production for ICs for free. The OEM pays for this one way or another. When you buy a standard analog IC, some portion of the price you pay is used to cover the development cost of that chip. The real question becomes, what portion of the price you pay is actually the cost to make the chip? A simplified analysis is derived by viewing a chip company’s financial statement. The critical metric is Gross Profit Margin (GPM).
Gross Profit = Company Annual Sales – Actual Cost to Build the Products Sold
When viewed in their annual report, reflecting sales over a 12 month period, GPM is an average, meaning half of the chip company’s sales during that year achieved more than the reported GPM and half were below the reported GPM.
Depending on the GPM of the products you selected for your new design, it may be cost advantageous to consider replacing them with an analog ASIC. For example, a circuit uses several off-the-shelf analog ICs, including a Linear Tech gain programmable precision instrumentation amplifier, a National micro power ultra low-dropout regulator, an Analog Devices 40 µA micropower instrumentation amplifier, and much more. The combined high volume bill of materials cost was $3.56 and was easy to integrate into an analog ASIC. By integrating the equivalent functions into an analog ASIC, it was possible to reduce the $3.56 cost to well under one dollar. The product lifetime is expected to be ten years, with monthly volumes averaging 15K units.
After amortizing in the NRE and tooling costs associated with the development of the ASIC, the following sensitivity analysis was developed. It is expected that during the lifetime of the ASIC that there may be some degradation to the prices of the standard analog ICs. The analysis projects lifetime savings based on not only under and over achievement of the lifetime volumes of the chip but also the fact the future cost savings may be less than today’s based standard product price changes.
While cost is a compelling reason to move to an analog ASIC because it is an easily measured metric, do not underestimate the value of IP protection and unique differentiation. Many times these critical aspects of an analog ASIC’s economic value are overlooked.
Information is shared by www.irvs.info
Analog ASICs are not for everyone. Like any component choice, they must offer the best economic value for the application. Any associated up-front NRE costs (non-recurring engineering) must be factored into the equation along with hard tooling (wafer fabrication masks, test hardware and software and more). In addition, there is the issue of time. Analog ASICs can take from six months up to a year or more to be ready to use in a production environment. And of course, there is a minimum quantity that must be consumed to assure the value is received. These must all align properly to justify development of an Analog ASIC
Why do Standard Analog ICs Cost So Much?
No one designs and tools production for ICs for free. The OEM pays for this one way or another. When you buy a standard analog IC, some portion of the price you pay is used to cover the development cost of that chip. The real question becomes, what portion of the price you pay is actually the cost to make the chip? A simplified analysis is derived by viewing a chip company’s financial statement. The critical metric is Gross Profit Margin (GPM).
Gross Profit = Company Annual Sales – Actual Cost to Build the Products Sold
When viewed in their annual report, reflecting sales over a 12 month period, GPM is an average, meaning half of the chip company’s sales during that year achieved more than the reported GPM and half were below the reported GPM.
Depending on the GPM of the products you selected for your new design, it may be cost advantageous to consider replacing them with an analog ASIC. For example, a circuit uses several off-the-shelf analog ICs, including a Linear Tech gain programmable precision instrumentation amplifier, a National micro power ultra low-dropout regulator, an Analog Devices 40 µA micropower instrumentation amplifier, and much more. The combined high volume bill of materials cost was $3.56 and was easy to integrate into an analog ASIC. By integrating the equivalent functions into an analog ASIC, it was possible to reduce the $3.56 cost to well under one dollar. The product lifetime is expected to be ten years, with monthly volumes averaging 15K units.
After amortizing in the NRE and tooling costs associated with the development of the ASIC, the following sensitivity analysis was developed. It is expected that during the lifetime of the ASIC that there may be some degradation to the prices of the standard analog ICs. The analysis projects lifetime savings based on not only under and over achievement of the lifetime volumes of the chip but also the fact the future cost savings may be less than today’s based standard product price changes.
While cost is a compelling reason to move to an analog ASIC because it is an easily measured metric, do not underestimate the value of IP protection and unique differentiation. Many times these critical aspects of an analog ASIC’s economic value are overlooked.
Information is shared by www.irvs.info
Thursday, July 14, 2011
3D modeling integrates flexible PCB design
Over the last decade, electronic products have become increasingly complex and dense as they support more functions into dramatically reduced footprints. The need for flexible circuits has grown exponentially, since they are often the preferred solution to achieve package weight-reduction, compared to rigid planar boards.
They are also easier to manufacture, reducing total assembly time while driving down cost and errors. Through their proven suitability for handling more than 25 point to point wires connections, flexible PCBs also provide greater system reliability.
Additionally, their main advantage is their ability to bend in order to accommodate the most cramped environments, enabling denser component layouts within the specified mechanical constraints of consumer products.
This makes flexible PCBs suitable for use in almost all electronics-based equipment, from consumer products such as digital cameras, computers and hard drives, to internal medical devices and military equipment.
Several generations of notebooks, tablet computers and other devices have been able to slim down while increasing their functionalities thanks to flexible layouts and interconnects.
Reducing the design cycle
Looking at how some flexible PCBs are designed today, and considering their development cycles, it is clear that there is considerable room for improvement. When Dassault Systèmes started to work on this subject with a leading Japanese worldwide consumer electronics company, we soon realized that their design process was slow, extremely complex and time consuming.
The first steps of the development process were purely manual and involved placing the flexible PCB assembly within the product. Even today, some companies are still making paper PCBs by hand, and check the components’ positions manually throughout the product’s physical mock up stages.
Following this procedure, 2D drawings were generated and shared with the ECAD designer for component placement and routing.
Within this outdated methodology, mechanical and electronic design processes were conducted separately. Only late in the development cycle was it possible to exchange critical design data between MCAD and ECAD systems. The limitations in data exchange and the lack of co-design functionality resulted in the need for additional design iterations, driving up development times and costs.
Information is shared by www.irvs.info
They are also easier to manufacture, reducing total assembly time while driving down cost and errors. Through their proven suitability for handling more than 25 point to point wires connections, flexible PCBs also provide greater system reliability.
Additionally, their main advantage is their ability to bend in order to accommodate the most cramped environments, enabling denser component layouts within the specified mechanical constraints of consumer products.
This makes flexible PCBs suitable for use in almost all electronics-based equipment, from consumer products such as digital cameras, computers and hard drives, to internal medical devices and military equipment.
Several generations of notebooks, tablet computers and other devices have been able to slim down while increasing their functionalities thanks to flexible layouts and interconnects.
Reducing the design cycle
Looking at how some flexible PCBs are designed today, and considering their development cycles, it is clear that there is considerable room for improvement. When Dassault Systèmes started to work on this subject with a leading Japanese worldwide consumer electronics company, we soon realized that their design process was slow, extremely complex and time consuming.
The first steps of the development process were purely manual and involved placing the flexible PCB assembly within the product. Even today, some companies are still making paper PCBs by hand, and check the components’ positions manually throughout the product’s physical mock up stages.
Following this procedure, 2D drawings were generated and shared with the ECAD designer for component placement and routing.
Within this outdated methodology, mechanical and electronic design processes were conducted separately. Only late in the development cycle was it possible to exchange critical design data between MCAD and ECAD systems. The limitations in data exchange and the lack of co-design functionality resulted in the need for additional design iterations, driving up development times and costs.
Information is shared by www.irvs.info
Tuesday, July 12, 2011
Microcontroller provides an alternative to DDS
Audio and low-frequency circuit systems often require a signal source with a pure spectrum. DDS (direct-digital-synthesis) devices often perform the signal generation by using these specialized integrated circuits. A DDS device uses a DAC but often with no more than 16-bit resolution, limiting the SNR (signal-to-noise ratio).
You can perform the same task with a microcontroller programmed as a DDS and use an external high-resolution DAC. To achieve 18 to 24 bits of resolution requires a large memory table containing the cosine function for any values of phase progression.
An alternative approach lets you use a standard microcontroller with a small memory and still implement an effective synthesizer. You can design a circuit to produce a sine wave using a scalable digital oscillator built with adder and multiplier block functions in a simple structure.
Figure 1 shows a microcontroller driving an audio DAC. To develop your code to generate a sine wave, the circuit in Figure 2 comprises two integrators with an analog feedback loop equivalent to that of an ideal resonator.
Parameter F defines the frequency and ranges from 0 to –0.2, and Parameter A sets the amplitude of the output signal with a single initial pulse at start-up. The following equation derives the frequency of generated signals:
where T denotes the time for computing an entire sequence to obtain output data.
The firmware for implementing this system is relatively straightforward. It requires just a few additions and one multiplication. Thus, you can use a slow microcontroller. Remember, though, that the precision of every operation must be adequate to warrant a complete signal reconstruction. Processing data with 8 or 16 bits isn’t sufficient. You must write your firmware to emulate a greater number of bits, which requires accurate code implementation.
If you properly develop your code, then you should generate the DAC output codes that produce a sine wave (Figure 3). Remember that Parameter F is nonlinear with respect to the output frequency. If you need a directly proportional rate, you can square the value of F before applying it to the input. You’ll find it useful when you need to make an easy frequency setting.
You can use just about any microcontroller to implement the oscillator, together with a high-performance DAC. You can achieve an output SNR greater than 110 dB. Many audio DACs operating in monophonic mode have 20- to 24-bit resolution at a 192-kHz sampling rate. They also offer a dynamic range of 120 dB or more.
Information is shared by www.irvs.info
You can perform the same task with a microcontroller programmed as a DDS and use an external high-resolution DAC. To achieve 18 to 24 bits of resolution requires a large memory table containing the cosine function for any values of phase progression.
An alternative approach lets you use a standard microcontroller with a small memory and still implement an effective synthesizer. You can design a circuit to produce a sine wave using a scalable digital oscillator built with adder and multiplier block functions in a simple structure.
Figure 1 shows a microcontroller driving an audio DAC. To develop your code to generate a sine wave, the circuit in Figure 2 comprises two integrators with an analog feedback loop equivalent to that of an ideal resonator.
Parameter F defines the frequency and ranges from 0 to –0.2, and Parameter A sets the amplitude of the output signal with a single initial pulse at start-up. The following equation derives the frequency of generated signals:
where T denotes the time for computing an entire sequence to obtain output data.
The firmware for implementing this system is relatively straightforward. It requires just a few additions and one multiplication. Thus, you can use a slow microcontroller. Remember, though, that the precision of every operation must be adequate to warrant a complete signal reconstruction. Processing data with 8 or 16 bits isn’t sufficient. You must write your firmware to emulate a greater number of bits, which requires accurate code implementation.
If you properly develop your code, then you should generate the DAC output codes that produce a sine wave (Figure 3). Remember that Parameter F is nonlinear with respect to the output frequency. If you need a directly proportional rate, you can square the value of F before applying it to the input. You’ll find it useful when you need to make an easy frequency setting.
You can use just about any microcontroller to implement the oscillator, together with a high-performance DAC. You can achieve an output SNR greater than 110 dB. Many audio DACs operating in monophonic mode have 20- to 24-bit resolution at a 192-kHz sampling rate. They also offer a dynamic range of 120 dB or more.
Information is shared by www.irvs.info
Saturday, July 9, 2011
Creating video that mimics human visual perception
Recent significant breakthroughs in core video processing techniques have nurtured video technology into one that looks aptly placed to contest the capabilities of the human visual system. For one, the last couple of decades have witnessed a phenomenal increase in the number of pixels accommodated by display systems, enabling the transition from standard-definition (SD) video to high-definition (HD) video.
Another noteworthy evolution is the stark enhancement in pixel quality, characterized by high dynamic range (HDR) systems as they elegantly displace their low dynamic range (LDR) equivalents.
Moreover, the intuitive approaches developed in the understanding of images to replicate the perceptual abilities of the human brain have met with encouraging successes, as have 3D video systems in their drive toward a total eclipse of their 2D counterparts.
These advanced techniques coerce toward a common purpose—to ensure the disappearance of boundaries between the real and digital worlds, achieved through the capture of videos that mimic the various aspects of human visual perception. These aspects fundamentally relate to video processing research in the fields of video capture, display technologies, data compression as well as understanding video content.
Video capture in 3D, HD and HDR
The two distinct technologies used in the capture of digital videos are the charge-coupled devices (CCD) and complementary metal-oxide-semiconductor (CMOS) image sensors, both of which convert light intensities into appropriate values of electric charges to be later processed as electronic signals.
Leveraging on a remarkable half-century of continued development, these technologies enable the capture of HD videos of exceptional quality. Nevertheless, in terms of HDR videos, these technologies pale in comparison to the capabilities of a typical human eye, itself boasting a dynamic range (the ratio of the brightest to darkest parts visible) of about 10000:1.
Existing digital camcorders can either only capture the brighter portions of a scene using short exposure durations or the darker portions using longer exposure durations.
Practically, this shortcoming can be circumvented with the use of multiple camcorders with one or two beam splitters, in which several video sequences are captured concurrently under different exposure settings.
Beam splitters allow for the simultaneous capture of identical LDR scenes, the best portions of which are then used to synthesize HDR videos. From a research perspective, the challenge is to achieve this feat of a higher dynamic range with the use of a single camcorder, albeit with an unavoidable but reasonable reduction in quality that is insignificantly perceivable.
Moreover, it is envisioned that HDR camcorders equipped with advanced image sensors may serve this purpose in the near future.
3D capture technologies widely employ stereoscopic techniques of obtaining stereo pairs using a two-view setup. Cameras are mounted side by side, with a separation typically equal to the distance between a person's pupils.
Exploiting the idea that views from distant objects arrive at each eye along the same line of sight, while those from closer objects arrive at different angles, realistic 3D images can be obtained from the stereoscopic image pair.
Multi-view technology, an alternative to stereoscopy, captures 3D scenes by recording several independent video streams using an array of cameras. Additionally, plenoptic cameras, which capture the light field of a scene, can also be used for multiview capture with a single main lens. The resulting views can then either be shown on multiview displays or stored for further processing.
Information is shared by www.irvs.info
Another noteworthy evolution is the stark enhancement in pixel quality, characterized by high dynamic range (HDR) systems as they elegantly displace their low dynamic range (LDR) equivalents.
Moreover, the intuitive approaches developed in the understanding of images to replicate the perceptual abilities of the human brain have met with encouraging successes, as have 3D video systems in their drive toward a total eclipse of their 2D counterparts.
These advanced techniques coerce toward a common purpose—to ensure the disappearance of boundaries between the real and digital worlds, achieved through the capture of videos that mimic the various aspects of human visual perception. These aspects fundamentally relate to video processing research in the fields of video capture, display technologies, data compression as well as understanding video content.
Video capture in 3D, HD and HDR
The two distinct technologies used in the capture of digital videos are the charge-coupled devices (CCD) and complementary metal-oxide-semiconductor (CMOS) image sensors, both of which convert light intensities into appropriate values of electric charges to be later processed as electronic signals.
Leveraging on a remarkable half-century of continued development, these technologies enable the capture of HD videos of exceptional quality. Nevertheless, in terms of HDR videos, these technologies pale in comparison to the capabilities of a typical human eye, itself boasting a dynamic range (the ratio of the brightest to darkest parts visible) of about 10000:1.
Existing digital camcorders can either only capture the brighter portions of a scene using short exposure durations or the darker portions using longer exposure durations.
Practically, this shortcoming can be circumvented with the use of multiple camcorders with one or two beam splitters, in which several video sequences are captured concurrently under different exposure settings.
Beam splitters allow for the simultaneous capture of identical LDR scenes, the best portions of which are then used to synthesize HDR videos. From a research perspective, the challenge is to achieve this feat of a higher dynamic range with the use of a single camcorder, albeit with an unavoidable but reasonable reduction in quality that is insignificantly perceivable.
Moreover, it is envisioned that HDR camcorders equipped with advanced image sensors may serve this purpose in the near future.
3D capture technologies widely employ stereoscopic techniques of obtaining stereo pairs using a two-view setup. Cameras are mounted side by side, with a separation typically equal to the distance between a person's pupils.
Exploiting the idea that views from distant objects arrive at each eye along the same line of sight, while those from closer objects arrive at different angles, realistic 3D images can be obtained from the stereoscopic image pair.
Multi-view technology, an alternative to stereoscopy, captures 3D scenes by recording several independent video streams using an array of cameras. Additionally, plenoptic cameras, which capture the light field of a scene, can also be used for multiview capture with a single main lens. The resulting views can then either be shown on multiview displays or stored for further processing.
Information is shared by www.irvs.info
Friday, July 8, 2011
Meters evolve to bring the smart grid home
The arrival of the truly connected digital home is one of the most anticipated events of the coming decade, promising tremendous opportunities across multiple markets. With stakeholders as diverse as consumer electronics manufacturers, connectivity solution providers, governmental agencies, utility companies and semiconductor suppliers, it is not surprising that there is a diversity of views on which direction the digital home should take.
Current stakeholders are looking to maintain existing business models, while new entrants see the connected home as an opportunity to create new revenue streams with products and services. Expect the digital home to be a battleground for years to come.
Many essentials, elemental building blocks are required to achieve the connected digital home. In the smart energy realm, the shift from mechanical meters to electronic meters is well under way.
Adding remote communications and automated service applications is the popular view of smart energy. The next envisioned frontier is the implementation of time-of-use plans, based on existing infrastructure and generation facilities. That limited vision, however, misses the opportunity to revolutionize the entire system, from power generation and distribution to effective energy consumption management.
"Smart meters will allow you to actually monitor how much energy your family is using by the month, by the week, by the day, or even by the hour," President Obama said in October 2009 during a speech in support of Recovery Act funding for smart grid technology. "Coupled with other technologies, this is going to help you manage your electricity use and your budget at the same time, allowing you to converse electricity during times when prices are highest."
That's a good starting point, but it will have no real impact on efficiency or consumption rates. Without fundamental energy generation and distribution innovation, consumers' behavior is unlikely to change in any significant way. Standardization and dynamic pricing are required to make it worthwhile for energy providers and consumers to monitor usage at so granular level.
The current, monopoly-driven infrastructure, however, is so inefficient that energy measurement and monitoring provide little opportunity for savings.
To achieve the benefits envisioned for the smart grid, full standards-based deployment is required.
A fully deployed smart grid will create a competitive energy service environment, with multiple providers and dynamic pricing, much as the telecom revolution has broadened customers' options over the past 25 years. A standards-based approach to supplying consumers' energy needs will drive investment in next-generation technologies and business models oriented to demographic profiles that match the efficiency generation profiles.
For example, people who work from home and consume a majority of their energy during the day may be offered an attractive package from an energy distributor partnered with a solar power generation company.
Information is shared by www.irvs.info
Current stakeholders are looking to maintain existing business models, while new entrants see the connected home as an opportunity to create new revenue streams with products and services. Expect the digital home to be a battleground for years to come.
Many essentials, elemental building blocks are required to achieve the connected digital home. In the smart energy realm, the shift from mechanical meters to electronic meters is well under way.
Adding remote communications and automated service applications is the popular view of smart energy. The next envisioned frontier is the implementation of time-of-use plans, based on existing infrastructure and generation facilities. That limited vision, however, misses the opportunity to revolutionize the entire system, from power generation and distribution to effective energy consumption management.
"Smart meters will allow you to actually monitor how much energy your family is using by the month, by the week, by the day, or even by the hour," President Obama said in October 2009 during a speech in support of Recovery Act funding for smart grid technology. "Coupled with other technologies, this is going to help you manage your electricity use and your budget at the same time, allowing you to converse electricity during times when prices are highest."
That's a good starting point, but it will have no real impact on efficiency or consumption rates. Without fundamental energy generation and distribution innovation, consumers' behavior is unlikely to change in any significant way. Standardization and dynamic pricing are required to make it worthwhile for energy providers and consumers to monitor usage at so granular level.
The current, monopoly-driven infrastructure, however, is so inefficient that energy measurement and monitoring provide little opportunity for savings.
To achieve the benefits envisioned for the smart grid, full standards-based deployment is required.
A fully deployed smart grid will create a competitive energy service environment, with multiple providers and dynamic pricing, much as the telecom revolution has broadened customers' options over the past 25 years. A standards-based approach to supplying consumers' energy needs will drive investment in next-generation technologies and business models oriented to demographic profiles that match the efficiency generation profiles.
For example, people who work from home and consume a majority of their energy during the day may be offered an attractive package from an energy distributor partnered with a solar power generation company.
Information is shared by www.irvs.info
Tuesday, July 5, 2011
Technological advances simplify personal healthcare and peak-performance training
Over the past few decades, medical electronics has played a key role in supporting personal disease management and simple and advanced diagnostics. Examples range from blood-glucose and blood-pressure monitoring devices to fever management with an electronic thermometer. Several innovations that focus on increasing quality of life for users are being made in this space. The considerable progress made in this area has prompted developers to look beyond personal healthcare for medical electronics applications.
A number of applications are emerging that use both conventional and new medical electronics in conjunction with advanced software intelligence known as biofeedback. Devices that incorporate this technology enable users to maintain health or to train for peak performance. Biofeedback already encompasses a diverse range of applications. Simple to complex biofeedback systems and modern semiconductor devices such as ultra-low-power microcontrollers (MCUs), high-end embedded processors, and high-performance analog front ends (AFEs) can contribute to unlimited innovations in the field of biofeedback.
Personal biofeedback device categories include neurofeedback with electroencephalogram (EEG) and hemoencephalogram (HEG), heart rate variability (HRV), stress and relaxation, electromyogram (EMG) muscle-activity feedback, skin temperature and core temperature measurement, and pulse oximetry. Notice that these are reuse and new-use versions of time-tested diagnostic technologies known to the healthcare industry. An increasing number of emerging fitness products are now geared toward enhancing performance as opposed to general-purpose fitness applications.
Information is shared by www.irvs.info
A number of applications are emerging that use both conventional and new medical electronics in conjunction with advanced software intelligence known as biofeedback. Devices that incorporate this technology enable users to maintain health or to train for peak performance. Biofeedback already encompasses a diverse range of applications. Simple to complex biofeedback systems and modern semiconductor devices such as ultra-low-power microcontrollers (MCUs), high-end embedded processors, and high-performance analog front ends (AFEs) can contribute to unlimited innovations in the field of biofeedback.
Personal biofeedback device categories include neurofeedback with electroencephalogram (EEG) and hemoencephalogram (HEG), heart rate variability (HRV), stress and relaxation, electromyogram (EMG) muscle-activity feedback, skin temperature and core temperature measurement, and pulse oximetry. Notice that these are reuse and new-use versions of time-tested diagnostic technologies known to the healthcare industry. An increasing number of emerging fitness products are now geared toward enhancing performance as opposed to general-purpose fitness applications.
Information is shared by www.irvs.info
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