Bioelectronics @ TU Delft

From the information below I feel that as researchers we need to develop cochlear implants (CIs) further. This I consider my duty!!

From "Events and Research in Speech, Language, and Hearing Disorders":

CI user’s mom said "I have a baby with CI and I wish researchers can find a very reliable way to do totally implanted CI, because I think people need hearing always and in each condition."

"I feel that we are placing to much hope into the development of a completely internal implant being released in our lifetime. I have a son who has bilateral implants and it would be amazing if he could swim, bathe, sleep and have sound during these activities. But the fact that he can have sound all of the other time is a modern-day miracle and we are so thankfull to all people putting in endless hours of research!"

"I’ve been fitted with a cochlear implant for about a year and still can’t really enjoy music. Will a new fully implantable one improve the sound quality and enable people to hear music?"

Cochlear Implant Swimming Youtube Video, Click here:

CI user’s mom said "Thanks for this video. Since I watched this video, I have taken my daughter swimming a lot more and she enjoys it way more than before. Before we would spend about 5-10 minutes in the pool. Now she wants to spend all day."

Wannaya/.

The brain is an amazing thing. That mysterious little jelly pudding up there in your head has an unsurpassed computing power that we all use everyday to at least some extent. Humans have always been amazed by the brain and there has been a strong trend throughout history to build machines which can take over some of that computing power.

From the first electronic computer Colossus (using 1500 vacuum tubes and used to crack the Enigma code during World War II) until recently the IBM Watson: a computer which is able to understand natural questions, which can perform reasoning based on a huge amount of information stored in its memory and can come up with the correct answer. And all that within 3 seconds.

Watson consists of 90 IBM Power 750 servers, 15 Terabytes of RAM, 2880 processor cores and can operate at 80 teraflops. Very impressive specifications. A couple of days ago Watson competed in a Jeopardy! game against two humans and he managed to win quite impressively (although he made one quite shameful mistake).

So does that mean that a bunch (ok, quite a big bunch) of processors can immitate the human brain? Well, to some degree it has proven it can. But the brain can do a lot more than understanding and answering questions. And besides functionality there is another factor, just like Dr. Bernard S. Meyerson, IBM’s vice president for innovation, mentioned: "The fact is that a human being is impossible to beat right now, in the sense of power efficiency, because you’ve got this little 20-watt thing, the brain, going up against many kilowatts."

So does this fact mean all the efforts made by the researchers are in vain? Definitely not, of course. It just means that we will have to keep using our little 20 watt miracle in order to come up with even smarter machines!

 Marijn van Dongen

The Journal of the American Medical Association will soon publish an article on the effects of the use of a cell phone on the glucose concentration in the region of the brain close to the antenna. According to the Preliminary Communication published today, the brain cells exposed to 50 minutes of radiation from the cell phone had a significant increase in their glucose metabolism of about 7 percent. Its clinical significance, however, is yet unknown.

Though I understand the clinical study conducted and the scientific method applied, there are some comments that I would like to vent.

The first one is about the state of the mobile phones used. The article mentions that they were on for 50 minutes. But what does "on" mean exactly? Were they just on standby, waiting for a call? Was a call being made? If so, for how long? Was there any data passed between the cell phone and its base station? But the total "talk time", or better, transmission time, is not revealed in the article.

Moreover, its is known that the amount of power transmitted by the cell phone depends on the distance to the base station. Fortunately, the cell phone decreases its output power when channel conditions are good enough, thereby extending its talk time and reducing co-channel interference. This thus implies that the amount of radiated power is another unknown in this study.

Finally, and this becomes evident from a literature study and experiments conducted by our own Mark Stoopman, the amount of energy being absorbed by brain tissue strongly depends on the frequency being used. This, in turn, depends on the type of service (GSM, UMTS, etc.) and the provider being used. GSM 1800, for instance, in use by, e.g., T-Mobile, leads to more tissue absorption than GSM 900.

All-in-all, a lot of unknows, if you ask me.

Wouter

The windmill is a beautiful artifact and very recognizable in the Dutch landscape. It converts wind energy into rotational motion, and is one of the earliest energy harvesters in history. Today, research on energy harvesting is not only focussing on generating megawatts of electrical power, but also deals with micropower harvesters that can for example be used to power small wireless sensors or RFID tags.

Micopower energy harvesters can convert energy from the environment (vibrations, thermal difference, solar, RF) into electrical energy that can be stored in a capacitor or battery.

This allows wireless sensors to transmit their payload once the harvester has collected enough energy. Thus, in principle, the wireless sensor can have an infinite lifetime. Of course, the amount of energy that can be harvested depends on the application. One of the reasons why micropower scavenged wireless sensors are not yet widely used today is that current radio solutions such as ZigBee or Bluetooth consume (much) more power than the harvester can deliver.

A promising solution for this problem is to use Ultra-WideBand communication. UWB radio makes use of carrierless, short duration pulses to transfer the information. Since the radio can be switched off during the time laps between two pulses, the average power consumption can be low enough so that it can be combined with an energy harvester. That’s why in this group we are working on energy scavenged UWB radios since they seem to be the perfect match. Another distinct advantage is that UWB communication can offer accurate localization within a few cm’s. This means that finding your missing car, laptop or wife will be a piece of cake without ever having to change the radio battery!

Mark Stoopman