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New LRC Study Evaluates the Effectiveness of Apple’s iPad Night Shift Application

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The light emitted by portable electronic devices (PEDs), particularly when used at night, has drawn a great deal of interest among sleep researchers, healthcare professionals, and the media. Research shows that exposure to light at night (LAN) may be associated with poor sleep and may lead to diminished alertness and performance throughout the day. Exposure to LAN can also acutely suppress melatonin, a hormone produced at night and in darkness, which tells the body it is nighttime. The short-wavelength “blue” light emitted by electronics can be especially disruptive to melatonin production, and the proximity to the eye when PEDs are in use only aggravates the threat to getting a good night’s sleep.In an effort to address this problem, in 2016 Apple Inc. released the Night Shift application for its line of PEDs, notably including the iPad, which in the third quarter of 2017 was the world’s most popular computer tablet and accounted for 25% of the year’s global tablet sales. The Night Shift mode permits users to change the screen’s color to “more warm” (i.e., less blue light) or “less warm” (i.e., more blue light), without necessarily changing its brightness. A new study from the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute investigated the effectiveness of Night Shift for lessening the impacts of nighttime iPad use on melatonin suppression, a marker of the circadian system. The study, to be published in 2018 by the peer-reviewed journal Lighting Research & Technology, is currently in press and is now available to subscribers online.In the study, LRC researchers Rohan Nagare, Barbara Plitnick, and Mariana G. Figueiro recruited 12 young adults to view iPads between 11:00 p.m. and 1:00 a.m. on four separate nights under four experimental conditions. One of the study’s conditions deliberately suppressed participants’ melatonin levels by delivering a blue light intervention to the participants’ eyes via light-emitting diode (LED) goggles designed by the LRC. A second condition occurred in dim light (< 5 lux), where participants wore orange goggles that filtered blue light, which served as the control for the baseline melatonin suppression calculations. The study also used two spectrally distinct lighting interventions for the iPad that were generated by adjusting the ‘color temperature’ slide control of the device’s Night Shift application to either extreme of its more warm (2837 K) or less warm (5997 K) range. LRC researchers independently measured the correlated color temperature (CCT) of each Night Shift setting as part of the study. Participants exposed to the Night Shift Low CCT (more warm) and Night Shift High CCT (less warm) interventions wore lensless eyeglasses frames fitted with an LRC-developed circadian light meter called a Dimesimeter, which measured eye-level light exposures. Data from the Dimesimeter was used to calculate the circadian stimulus (CS) received by participants during the experiment. Using the LRC’s free, downloadable CS Calculator, LRC researchers were able to closely predict the amount of melatonin suppression that was recorded for the participants.Results showed that all three lighting interventions significantly suppressed melatonin over the two hours of each study night. More importantly, there was no significant difference between the effectiveness of the two Night Shift settings. For a two-hour exposure to the iPad, the LRC measured: – 23% melatonin suppression on regular settings (not using Night Shift; from previous Wood et al. study) -19% melatonin suppression while using Night Shift High CCT -12% melatonin suppression while using Night Shift Low CCT  The study’s main takeaway is that changing screen color alone is insufficient for limiting the impact of PEDs on melatonin levels in the evening, and that screen brightness should also be reduced. Overall, the results of this LRC study may be useful for developers, manufacturers, and users of self-luminous electronic devices by emphasizing considerations other than light spectrum when designing and using display applications for health and wellbeing. In addition to spectral properties, LRC researchers recommend that users also consider lowering the amount of light emitted by PEDs by keeping light levels low, limiting the use of PEDs to one-hour sessions, and avoiding exposures starting at least two hours before bedtime. Better yet, LRC researchers recommend turning off PEDs at least two hours prior to desired bedtimes. Even if melatonin is not suppressed during this interval, these devices can be alerting to the brain and, as a result, can disrupt sleep.
About the Lighting Research Center
The Lighting Research Center (LRC) at Rensselaer Polytechnic Institute is the world’s leading center for lighting research and education. Established in 1988 by the New York State Energy Research and Development Authority (NYSERDA), the LRC conducts research in light and human health, transportation lighting and safety, solid-state lighting, energy efficiency, and plant health. LRC lighting scientists with multidisciplinary expertise in research, technology, design, and human factors, collaborate with a global network of leading manufacturers and government agencies, developing innovative lighting solutions for projects that range from the Boeing 787 Dreamliner to U.S. Navy submarines to hospital neonatal intensive-care units. In 1990, the LRC became the first university research center to offer graduate degrees in lighting and today, offers a M.S. in lighting and a Ph.D. to educate future leaders in lighting. Learn more at www.lrc.rpi.edu.About Rensselaer Polytechnic Institute
Founded in 1824, Rensselaer Polytechnic Institute is America’s first technological research university. Rensselaer encompasses five schools, 32 research centers, more than 145 academic programs, and a dynamic community made up of more than 7,900 students and more than 100,000 living alumni. Rensselaer faculty and alumni include more than 145 National Academy members, six members of the National Inventors Hall of Fame, six National Medal of Technology winners, five National Medal of Science winners, and a Nobel Prize winner in Physics. With nearly 200 years of experience advancing scientific and technological knowledge, Rensselaer remains focused on addressing global challenges with a spirit of ingenuity and collaboration.

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Samsung rolls out beta version of ethereum blockchain development kit

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South Korean electronics giant Samsung has released a beta version of ethereum blockchain-based software development kit (SDK) for partner developers.

The kit provides “a full set” of functions that are required to build decentralized apps (dapps), the company said, adding that it also offers a payment gateway for cryptocurrency remittance with its user interface.

“Samsung Blockchain SDK is available to communicate with external blockchain node providing payment solution. It can reduce costs to build your dapp except in case if you have your own wallet logics already,” Samsung explained.

The kit currently only supports five devices: Galaxy S10e, S10, S10+, S10 5G and the Galaxy Fold. The official version of the kit is expected to be released by the end of this year.

Galaxy S10 was launched earlier this year, which supports several dapps as well as features a Samsung crypto wallet supporting ether and ERC20 tokens. The giant was also planning to bring blockchain solutions to more budget-friendly Galaxy models.

Recently, there were also reports that Samsung is creating its own Ethereum-based blockchain network and may be planning to issue its own token too.

Source: https://www.theblockcrypto.com/tiny/samsung-rolls-out-beta-version-of-ethereum-blockchain-development-kit/

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How you charge your mobile phone could compromise its battery lifespan

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Researchers at WMG at the University of Warwick have found that use of inductive charging, whilst highly convenient, risks depleting the life of mobile phones using typical LIBs (Lithium-ion batteries)

Consumers and manufacturers have ramped up their interest in this convenient charging technology, abandoning fiddling with plugs and cables in a favour of just setting the phone directly on a charging base.

Standardisation of charging stations, and inclusion of inductive charging coils in many new smartphones has led to rapidly increasing adoption of the technology. In 2017, 15 automobile models announced the inclusion of consoles within vehicles for inductively charging consumer electronic devices, such as smartphones — and at a much larger scale, many are considering it for charging electric vehicle batteries.

Inductive charging enables a power source to transmit energy across an air gap, without the use of connecting wire but one of the main issues with this mode of charging is the amount of unwanted and potentially damaging heat that can be generated. There are several sources of heat generation associated with any inductive charging system — in both the charger and the device being charged. This additional heating is made worse by the fact that the device and the charging base are in close physical contact, any heat generated in one device may be transferred to the other by simple thermal conduction and convection.

In a smartphone, the power receiving coil is close to the back cover of the phone (which is usually electrically nonconductive) and packaging constraints necessitate placement of the phone’s battery and power electronics in close proximity, with limited opportunities to dissipate heat generated in the phone, or shield the phone from heat generated by the charger. It has been well-documented that batteries age more quickly when stored at elevated temperatures and that exposure to higher temperatures can thus significantly influence the state-of-health (SoH) of batteries over their useful lifetime.

The rule of thumb (or more technically the Arrhenuis equation) is that for most chemical reactions, the reaction rate doubles with each 10 °C rise in temperature. In a battery, the reactions which can occur include the accelerated growth rate of passivating films (a thin inert coating making the surface underneath unreactive) on the cell’s electrodes. This occurs by way of cell redox reactions, which irreversibly increase the internal resistance of the cell, ultimately resulting in performance degradation and failure. A lithium ion battery dwelling above 30 °C is typically considered to be at elevated temperature exposing the battery to risk of a shortened useful life.

Guidelines issued by battery manufacturers also specify that the upper operational temperature range of their products should not surpass the 50?60 °C range to avoid gas generation and catastrophic failure.

These facts led WMG researchers to carry out experiments comparing the temperature rises in normal battery charging by wire with inductive charging. However the WMG were even more interested in inductive charging when the consumer misaligns the phone on the charging base. To compensate for poor alignment of the phone and the charger, inductive charging systems typically increase the transmitter power and/or adjust their operating frequency, which incurs further efficiency losses and increases heat generation.

This misalignment can be a very common occurrence as the actual position of the receiving antenna in the phone is not always intuitive or obvious to the consumer using the phone. The WMG research team therefore also tested phone charging with deliberate misalignment of transmitter and receiver coils.

All three charging methods (wire, aligned inductive and misaligned inductive) were tested with simultaneous charging and thermal imaging over time to generate temperature maps to help quantify the heating effects. The results of those experiments have been published in the journal ACS Energy Letters in an article entitled “Temperature Considerations for Charging Li-Ion Batteries: Inductive versus Mains Charging Modes for Portable Electronic Devices.”

The graphics with this press release illustrates three modes of charging, based on (a) AC mains charging (cable charging) and inductive charging when coils are (b) aligned and (c) misaligned. Panels i and ii show a realistic view of the charging modes with a snapshot of the thermal maps of the phone after 50 min of charging. Regardless of the mode of charging, the right edge of the phone showed a higher rate of increase in temperature than other areas of the phone and remained higher throughout the charging process. A CT scan of the phone showed that this hotspot is where the motherboard is located

  • In the case of the phone charged with conventional mains power, the maximum average temperature reached within 3 hours of charging did not exceed 27 °C.
  • In contrast this for the phone charged by aligned inductive charging, the temperature peaked at 30.5 °C but gradually reduced for the latter half of the charging period. This is similar to the maximum average temperature observed during misaligned inductive charging.
  • In the case of misaligned inductive charging, the peak temperature was of similar magnitude (30.5 °C) but this temperature was reached sooner and persisted for much longer at this level (125 minutes versus 55 minutes for properly aligned charging).

Also noteworthy was the fact that the maximum input power to the charging base was greater in the test where the phone was misaligned (11W) than the well-aligned phone (9.5 W). This is due to the charging system increasing the transmitter power under misalignment in order to maintain target input power to the device. The maximum average temperature of the charging base while charging under misalignment reached 35.3 °C, two degrees higher than the temperature detected when the phone was aligned, which achieved 33 °C. This is symptomatic of deterioration in system efficiency, with additional heat generation attributable to power electronics losses and eddy currents.

The researchers do note that future approaches to inductive charging design can diminish these transfer losses, and thus reduce heating, by using ultrathin coils, higher frequencies, and optimized drive electronics to provide chargers and receivers that are compact and more efficient and can be integrated into mobile devices or batteries with minimal change.

In conclusion, the research team found that inductive charging, whilst convenient, will likely lead to a reduction in the life of the mobile phone battery. For many users, this degradation may be an acceptable price for the convenience of charging, but for those wishing to eke out the longest life from their phone, cable charging is still recommended.

Source: https://www.sciencedaily.com/releases/2019/06/190626124943.htm

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Surprise! Many Americans don’t know what phone they own, think it has 5G

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According to survey results published by refurbished products site Decluttr, many smartphone users based in the United States don’t know very much about their own phones.

Decluttr’s survey polled 2,000 U.S.-based smartphone owners of all ages (18+). The results present a sobering look at just how little smartphone users seem to care about what phone they’re using, how it works, or what features it does or does not have.

Probably the most overall surprising result of the survey is that only about half of respondents were able to correctly identify their current smartphone when shown a promotional image of that phone amongst other phones from the same manufacturer.

Diving further into that, it appears smartphone users with Samsung Galaxy S line devices are much better at recognizing their phones as compared to Apple iPhone owners. Check out the graph below:

A chart showing how many smartphone users can correctly identify their own smartphone.

However, just because Samsung owners are good at identifying which phone they own doesn’t mean they are good at knowing what their phone does. According to the survey, around 40 percent of Samsung Galaxy S owners are completely unaware their device supports wireless charging.

On the Apple front, only 14 percent of iPhone owners know their phone features an NFC chip and only a little less than half of iPhone users know their smartphone is water resistant.

The most alarming result from the survey is how many people think their smartphone supports 5G connections. About one-third of respondents think their smartphone can connect to a 5G network, even though it most certainly cannot. What’s worse, of those people who say their phone is 5G ready, a whopping 62 percent say that they’ve seen a notable speed increase while using 5G — even though they have likely never seen 5G service.

Survey results showing how many smartphone users think they have 5G service.

The rest of Decluttr’s survey results focus on misconceptions smartphone users have when it comes to buying refurbished devices, which naturally ties in well to the company’s business. You can see the full page of survey results here.

Source: https://www.androidauthority.com/smartphone-users-survey-2019-1004535/

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